Systems and Methods for Providing Tunable Warm White Light

ABSTRACT

The present disclosure provides methods for generating tunable white light. The methods include using a plurality of LED strings to generate light with color points that fall within white, red, and cyan color ranges, with each LED string being driven with a separately controllable drive current in order to tune the generated light output.

CROSS-REFERENCE PARAGRAPH

This application is a continuation of U.S. patent application Ser. No.16/049,786 filed Jul. 30, 2018, which is a continuation-in-part ofInternational Patent Application No. PCT/US2016/047233 filed Aug. 16,2017; a continuation-in-part of International Patent Application No.PCT/US2016/015402 filed Jan. 28, 2016; a continuation-in-part ofInternational Patent Application No. PCT/US2016/015348 filed Jan. 28,2016; a continuation-in-part of International Patent Application No.PCT/US2016/015368 filed Jan. 28, 2016; and a continuation-in-part ofInternational Patent Application No. PCT/US2016/015318 filed Jan. 28,2016, the contents of which are incorporated in their entirety as iffully set forth herein.

FIELD OF THE DISCLOSURE

This disclosure is in the field of solid-state lighting. In particular,the disclosure relates to methods and devices for use in providingtunable white light with high color rendering and circadian stimulusperformance.

BACKGROUND

A wide variety of light emitting devices are known in the art including,for example, incandescent light bulbs, fluorescent lights, andsemiconductor light emitting devices such as light emitting diodes(“LEDs”).

There are a variety of resources utilized to describe the light producedfrom a light emitting device, one commonly used resource is 1931 CIE(Commission Internationale de l'Eclairage) Chromaticity Diagram. The1931 CIE Chromaticity Diagram maps out the human color perception interms of two CIE parameters x and y. The spectral colors are distributedaround the edge of the outlined space, which includes all of the huesperceived by the human eye. The boundary line represents maximumsaturation for the spectral colors, and the interior portion representsless saturated colors including white light. The diagram also depictsthe Planckian locus, also referred to as the black body locus (BBL),with correlated color temperatures, which represents the chromaticitycoordinates (i.e., color points) that correspond to radiation from ablack-body at different temperatures. Illuminants that produce light onor near the BBL can thus be described in terms of their correlated colortemperatures (CCT). These illuminants yield pleasing “white light” tohuman observers, with general illumination typically utilizing CCTvalues between 1,800 K and 10,000 K.

Color rendering index (CRI) is described as an indication of thevibrancy of the color of light being produced by a light source. Inpractical terms, the CRI is a relative measure of the shift in surfacecolor of an object when lit by a particular lamp as compared to areference light source, typically either a black-body radiator or thedaylight spectrum. The higher the CRI value for a particular lightsource, the better that the light source renders the colors of variousobjects it is used to illuminate.

LEDs have the potential to exhibit very high power efficiencies relativeto conventional incandescent or fluorescent lights. Most LEDs aresubstantially monochromatic light sources that appear to emit lighthaving a single color. Thus, the spectral power distribution (“SPD”) ofthe light emitted by most LEDs is tightly centered about a “peak”wavelength, which is the single wavelength where the spectral powerdistribution or “emission spectrum” of the LED reaches its maximum asdetected by a photo-detector. LEDs typically have a full-widthhalf-maximum wavelength range of about 10 nm to 30 nm, comparativelynarrow with respect to the broad range of visible light to the humaneye, which ranges from approximately from 380 nm to 800 nm.

In order to use LEDs to generate white light, LED lamps have beenprovided that include two or more LEDs that each emit a light of adifferent color. The different colors combine to produce a desiredintensity and/or color of white light. For example, by simultaneouslyenergizing red, green and blue LEDs, the resulting combined light mayappear white, or nearly white, depending on, for example, the relativeintensities, peak wavelengths and spectral power distributions of thesource red, green and blue LEDs. The aggregate emissions from red,green, and blue LEDs typically provide poor CRI for general illuminationapplications due to the gaps in the spectral power distribution inregions remote from the peak wavelengths of the LEDs.

White light may also be produced by utilizing one or more luminescentmaterials such as phosphors to convert some of the light emitted by oneor more LEDs to light of one or more other colors. The combination ofthe light emitted by the LEDs that is not converted by the luminescentmaterial(s) and the light of other colors that are emitted by theluminescent material(s) may produce a white or near-white light.

LED lamps have been provided that can emit white light with differentCCT values within a range. Such lamps utilize two or more LEDs, with orwithout luminescent materials, with respective drive currents that areincreased or decreased to increase or decrease the amount of lightemitted by each LED. By controllably altering the power to the variousLEDs in the lamp, the overall light emitted can be tuned to differentCCT values. The range of CCT values that can be provided with adequateCRI values and efficiency is limited by the selection of LEDs.

The spectral profiles of light emitted by white artificial lighting canimpact circadian physiology, alertness, and cognitive performancelevels. Bright artificial light can be used in a number of therapeuticapplications, such as in the treatment of seasonal affective disorder(SAD), certain sleep problems, depression, jet lag, sleep disturbancesin those with Parkinson's disease, the health consequences associatedwith shift work, and the resetting of the human circadian clock.Artificial lighting may change natural processes, interfere withmelatonin production, or disrupt the circadian rhythm. Blue light mayhave a greater tendency than other colored light to affect livingorganisms through the disruption of their biological processes which canrely upon natural cycles of daylight and darkness. Exposure to bluelight late in the evening and at night may be detrimental to one'shealth.

Significant challenges remain in providing LED lamps that can providewhite light across a range of CCT values while simultaneously achievinghigh efficiencies, high luminous flux, good color rendering, andacceptable color stability. It is also a challenge to provide lightingapparatuses that can provide desirable lighting performance whileallowing for the control of circadian energy performance.

DISCLOSURE

The present disclosure provides aspects of semiconductor light emittingdevices comprising a first light emitting diode (“LED”) string thatcomprises a first LED that has a first recipient luminophoric mediumthat comprises a first luminescent material, a second LED string thatcomprises a second LED that has a second recipient luminophoric mediumthat comprises a second luminescent material, a third LED string thatcomprises a third LED that has a third recipient luminophoric mediumthat comprises a third luminescent material, and a drive circuit. Thedrive circuit may be responsive to input from one or more of an end userof the semiconductor light emitting device and one or more sensorsmeasuring a characteristic associated with the performance of thesemiconductor light emitting device. In some implementations the firstLED and first luminophoric medium together emit a first unsaturatedlight having a first color point within a white color range, the secondLED and second luminophoric medium together emit a second unsaturatedlight having a second color point within a red color range, and thethird LED and third luminophoric medium together emit a thirdunsaturated light having a third color point within a cyan color range.In some implementations, the first unsaturated light can have a colorpoint between about 3500 K and about 6500 K CCT value along the Plackianlocus. In some implementations the drive circuit is configured to adjustthe relative values of first, second, and third drive currents providedto the LEDs in the first, second, and third LED strings, respectively,to adjust a fourth color point of a fourth unsaturated light thatresults from a combination of the first, second, and third unsaturatedlight. In some implementations of the devices of the present disclosurethe red color range can be defined by the spectral locus between theconstant CCT line of 1600 K and the line of purples, the line ofpurples, a line connecting the ccx, ccy color coordinates (0.61, 0.21)and (0.47, 0.28), and the constant CCT line of 1600 K, the cyan colorrange can be defined by a line connecting the ccx, ccy color coordinates(0.18, 0.55) and (0.27, 0.72), the constant CCT line of 9000 K, thePlanckian locus between 9000 K and 1800 K, the constant CCT line of 1800K, and the spectral locus, and the white color range can be defined by apolygonal region on the 1931 CIE Chromaticity Diagram defined by thefollowing ccx, ccy color coordinates: (0.4006, 0.4044), (0.3736,0.3874), (0.3670, 0.3578), (0.3898, 0.3716). In some implementations ofthe devices of the present disclosure the LEDs in the first, second, andthird LED strings comprise blue LEDs having a peak wavelength betweenabout 405 nm and about 485 nm. In certain implementations of the devicesof the present disclosure the LEDs in the third LED string comprise LEDshaving a peak wavelength between about 440 nm and about 465 nm. In someimplementations the red color range comprises a region on the 1931 CIEChromaticity Diagram defined by a 20-step MacAdam ellipse at 1200 K, 20points below the Planckian locus, the cyan color range comprises aregion on the 1931 CIE Chromaticity Diagram defined by the regionbounded by (0.360, 0.495), (0.371, 0.518), (0.388, 0.522), and (0.377,0.499), and the white color range comprises a single 5-step MacAdamellipse with center point (0.3818, 0.3797) with a major axis “a” of0.01565, minor axis “b” of 0.00670, with an ellipse rotation angle θ of52.70°. In some implementations the devices of the present disclosurecomprise a drive circuit is configured to adjust the fourth color pointso that it falls within a 7-step MacAdam ellipse around any point on theblack body locus having a correlated color temperature between about1800 K and about 3200 K, and in some of these implementations the lightemitting devices are configured to generate the fourth unsaturated lightcorresponding to a plurality of points along a predefined path with thelight generated at each point having light with one or more of Ragreater than or equal to about 90 and R9 greater than or equal to about60; one or more of Rf greater than or equal to 75, Rf greater than orequal to about 80, Rf greater than or equal to about 90, Rf greater thanabout 95, Rf equal to about 100, Rg greater than or equal to about 80and less than or equal to about 120, Rg greater than or equal to about90 and less than or equal to about 110, Rg greater than or equal toabout 95 and less than or equal to about 105, or Rg equal to about 100;or both. In some implementations the devices comprise a drive circuitconfigured to adjust the fourth color point so that it falls within a7-step MacAdam ellipse around any point on the black body locus having acorrelated color temperature between about 1800 K and about 3000 K, andthe light emitting devices are configured to generate the fourthunsaturated light corresponding to a plurality of points along apredefined path with the light generated at each point having light withone or more of Ra greater than or equal to about 90 and R9 greater thanor equal to about 65; one or more of Rf greater than or equal to 85, Rfgreater than or equal to about 86, Rf greater than or equal to about 87,Rf greater than about 88, Rf greater than about 89, Rf greater thanabout 90, Rf equal to about 100, Rg greater than or equal to about 80and less than or equal to about 120, Rg greater than or equal to about90 and less than or equal to about 110, Rg greater than or equal toabout 95 and less than or equal to about 105, or Rg equal to about 100;or both. In some implementations the devices comprise a drive circuitconfigured to adjust the fourth color point so that it falls within a7-step MacAdam ellipse around any point on the black body locus having acorrelated color temperature between about 2000 K and about 3200 K, andthe light emitting devices are configured to generate the fourthunsaturated light corresponding to a plurality of points along apredefined path with the light generated at each point having light withone or more of Rf greater than or equal to about 80, Rf greater than orequal to about 90, Rf greater than about 95, Rf equal to about 100, Rggreater than or equal to about 80 and less than or equal to about 120,Rg greater than or equal to about 90 and less than or equal to about110, Rg greater than or equal to about 95 and less than or equal toabout 105, or Rg equal to about 100.

The present disclosure provides aspects of methods of forming a lightemitting apparatus, the methods comprising providing a substrate,mounting a first LED, a second LED, and a third LED on the substrate,providing first, second, and third luminophoric mediums in illuminativecommunication with the first, second, and third LEDs, respectively,wherein a combined light emitted by the first, second, and third LEDsand the first, second, and third luminophoric mediums together has afourth color point that falls within a 7-step MacAdam ellipse around anypoint on the black body locus having a correlated color temperaturebetween 1800 K and 3200 K. In some implementations, the methods compriseproviding a first LED and a first luminophoric medium configured to emitcombined light having a first color point within a white color rangedefined by a polygonal region on the 1931 CIE Chromaticity Diagramdefined by the following ccx, ccy color coordinates: (0.4006, 0.4044),(0.3736, 0.3874), (0.3670, 0.3578), (0.3898, 0.3716), providing a secondLED and a second luminophoric medium configured to emit combined lighthaving a second color point within a red color range defined by thespectral locus between the constant CCT line of 1600 K and the line ofpurples, the line of purples, a line connecting the ccx, ccy colorcoordinates (0.61, 0.21) and (0.47, 0.28), and the constant CCT line of1600 K, and providing a third LED and a third luminophoric mediumconfigured to emit combined light having a third color point within acyan color range defined by a line connecting the ccx, ccy colorcoordinates (0.18, 0.55) and (0.27, 0.72), the constant CCT line of 9000K, the Planckian locus between 9000 K and 1800 K, the constant CCT lineof 1800 K, and the spectral locus. In some implementations, the methodscomprise providing the first, second, and third LEDs and luminophoricmediums as phosphor-coated blue light emitting device chips. In someimplementations the first, second, and third luminophoric mediums areprovided in positions remotely located from the first, second, and thirdLEDs. In certain implementations, the third LED is provided as an LEDhaving a peak wavelength between about 440 nm and about 465 nm.

The present disclosure provides methods of generating white light, themethods comprising producing light from a first light emitting diode(“LED”) string that comprises a blue LED with a peak wavelength ofbetween about 405 nm and about 470 nm, producing light from a secondlight emitting diode (“LED”) string that comprises a blue LED with apeak wavelength of between about 405 nm and about 470 nm, producinglight from a third light emitting diode (“LED”) string that comprises ablue LED with a peak wavelength of between about 405 nm and about 470nm, passing the light produced by each of the first, second, and thirdLED strings through one of a plurality of respective luminophoricmediums to produce a first unsaturated light, a second unsaturatedlight, and a third unsaturated light, respectively, and combining thefirst unsaturated light, the second unsaturated light, and the thirdunsaturated light together into a fourth unsaturated light. In certainimplementations, the first unsaturated light has a first color pointbetween about 3500 K and about 6500 K CCT value along the Plackianlocus. In some implementations, the first unsaturated light is providedwith a first color point that is a within a white color range defined bya polygonal region on the 1931 CIE Chromaticity Diagram defined by thefollowing ccx, ccy color coordinates: (0.4006, 0.4044), (0.3736,0.3874), (0.3670, 0.3578), (0.3898, 0.3716). In certain implementations,the second unsaturated light is provided with a second color pointwithin a red color range defined by the spectral locus between theconstant CCT line of 1600 K and the line of purples, the line ofpurples, a line connecting the ccx, ccy color coordinates (0.61, 0.21)and (0.47, 0.28), and the constant CCT line of 1600 K. In someimplementations, the third unsaturated light is provided with a thirdcolor point within a cyan color range defined by a line connecting theccx, ccy color coordinates (0.18, 0.55) and (0.27, 0.72), the constantCCT line of 9000 K, the Planckian locus between 9000 K and 1800 K, theconstant CCT line of 1800 K, and the spectral locus. In someimplementations, the fourth unsaturated light corresponds to at leastone of a plurality of points along a predefined path near the black bodylocus in the 1931 CIE Chromaticity Diagram within a 7-step MacAdamellipse around any point on the black body locus having a correlatedcolor temperature between about 1800 K and about 3200 K. In someimplementations, the methods comprise generating the fourth unsaturatedlight corresponding to a plurality of points along a predefined pathwith the light generated at each point having light with one or more ofRa greater than or equal to about 90 and R9 greater than or equal toabout 65; one or more of Rf greater than or equal to 85, Rf greater thanor equal to about 86, Rf greater than or equal to about 87, Rf greaterthan about 88, Rf greater than about 89, Rf greater than about 90, Rfequal to about 100, Rg greater than or equal to about 80 and less thanor equal to about 120, Rg greater than or equal to about 90 and lessthan or equal to about 110, Rg greater than or equal to about 95 andless than or equal to about 105, or Rg equal to about 100; or both.

The general disclosure and the following further disclosure areexemplary and explanatory only and are not restrictive of thedisclosure, as defined in the appended claims. Other aspects of thepresent disclosure will be apparent to those skilled in the art in viewof the details as provided herein. In the figures, like referencenumerals designate corresponding parts throughout the different views.All callouts and annotations are hereby incorporated by this referenceas if fully set forth herein.

DRAWINGS

The summary, as well as the following detailed description, is furtherunderstood when read in conjunction with the appended drawings. For thepurpose of illustrating the disclosure, there are shown in the drawingsexemplary implementations of the disclosure; however, the disclosure isnot limited to the specific methods, compositions, and devicesdisclosed. In addition, the drawings are not necessarily drawn to scale.In the drawings:

FIG. 1 illustrates aspects of light emitting devices according to thepresent disclosure;

FIG. 2 illustrates aspects of light emitting devices according to thepresent disclosure;

FIG. 3 depicts a graph of a 1931 CIE Chromaticity Diagram illustratingthe location of the Planckian locus;

FIG. 4 illustrates some aspects of light emitting devices according tothe present disclosure, including some suitable color ranges for lightgenerated by components of the devices;

FIG. 5 illustrates some aspects of light emitting devices according tothe present disclosure, including some suitable color ranges for lightgenerated by components of the devices;

FIG. 6 illustrates some aspects of light emitting devices according tothe present disclosure, including some suitable color ranges for lightgenerated by components of the devices;

FIG. 7 illustrates some aspects of light emitting devices according tothe present disclosure, including some suitable color ranges for lightgenerated by components of the devices;

FIG. 8 illustrates aspects of light emitting devices according to thepresent disclosure; and

FIG. 9 illustrates aspects of light emitting devices according to thepresent disclosure.

All descriptions and callouts in the Figures are hereby incorporated bythis reference as if fully set forth herein.

FURTHER DISCLOSURE

The present disclosure may be understood more readily by reference tothe following detailed description taken in connection with theaccompanying figures and examples, which form a part of this disclosure.It is to be understood that this disclosure is not limited to thespecific devices, methods, applications, conditions or parametersdescribed and/or shown herein, and that the terminology used herein isfor the purpose of describing particular exemplars by way of exampleonly and is not intended to be limiting of the claimed disclosure. Also,as used in the specification including the appended claims, the singularforms “a,” “an,” and “the” include the plural, and reference to aparticular numerical value includes at least that particular value,unless the context clearly dictates otherwise. The term “plurality”, asused herein, means more than one. When a range of values is expressed,another exemplar includes from the one particular value and/or to theother particular value. Similarly, when values are expressed asapproximations, by use of the antecedent “about,” it will be understoodthat the particular value forms another exemplar. All ranges areinclusive and combinable.

It is to be appreciated that certain features of the disclosure whichare, for clarity, described herein in the context of separate exemplar,may also be provided in combination in a single exemplaryimplementation. Conversely, various features of the disclosure that are,for brevity, described in the context of a single exemplaryimplementation, may also be provided separately or in anysubcombination. Further, reference to values stated in ranges includeeach and every value within that range.

In one aspect, the present disclosure provides semiconductor lightemitting devices 100 that can have a plurality of light emitting diode(LED) strings. Each LED string can have one, or more than one, LED. Asdepicted schematically in FIG. 1, the device 100 may comprise one ormore LED strings (101A/101B/101C) that emit light (schematically shownwith arrows). In some instances, the LED strings can have recipientluminophoric mediums (102A/102B/102C) associated therewith. The lightemitted from the LED strings, combined with light emitted from therecipient luminophoric mediums, can be passed through one or moreoptical elements 103. Optical elements 103 may be one or more diffusers,lenses, light guides, reflective elements, or combinations thereof.

A recipient luminophoric medium 102A, 102B, or 102C includes one or moreluminescent materials and is positioned to receive light that is emittedby an LED or other semiconductor light emitting device. In someimplementations, recipient luminophoric mediums include layers havingluminescent materials that are coated or sprayed directly onto asemiconductor light emitting device or on surfaces of the packagingthereof, and clear encapsulants that include luminescent materials thatare arranged to partially or fully cover a semiconductor light emittingdevice. A recipient luminophoric medium may include one medium layer orthe like in which one or more luminescent materials are mixed, multiplestacked layers or mediums, each of which may include one or more of thesame or different luminescent materials, and/or multiple spaced apartlayers or mediums, each of which may include the same or differentluminescent materials. Suitable encapsulants are known by those skilledin the art and have suitable optical, mechanical, chemical, and thermalcharacteristics. In some implementations, encapsulants can includedimethyl silicone, phenyl silicone, epoxies, acrylics, andpolycarbonates. In some implementations, a recipient luminophoric mediumcan be spatially separated (i.e., remotely located) from an LED orsurfaces of the packaging thereof. In some implementations, such spatialsegregation may involve separation of a distance of at least about 1 mm,at least about 2 mm, at least about 5 mm, or at least about 10 mm. Incertain embodiments, conductive thermal communication between aspatially segregated luminophoric medium and one or more electricallyactivated emitters is not substantial. Luminescent materials can includephosphors, scintillators, day glow tapes, nanophosphors, inks that glowin visible spectrum upon illumination with light, semiconductor quantumdots, or combinations thereof.

In certain implementations, the recipient luminophoric mediums can beprovided as volumetric light converting elements having luminescentmaterials dispersed throughout a volume of matrix material. Eachvolumetric light converting element can be provided within at least aportion of a reflective cavity disposed above a semiconductor lightemitting device. In some implementations, each volumetric lightconverting element can be provided as spatially separated from the topsurface of the associated semiconductor light emitting device, with avoid or air gap between the volumetric light converting element and theassociated semiconductor light emitting device. In otherimplementations, each volumetric light converting element can beprovided within substantially all of a reflective cavity such that thebottom surface of each volumetric light converting element is adjacentto the top surface of the associated LED. In some implementations, anindex matching compound can be provided between the adjacent surfaces toavoid any voids or air gaps between the surfaces so that the lightemitted by the LED may pass from the LED to the volumetric lightconverting element with minimized reflection and refraction. Suitableimplementations of volumetric light converting elements are more fullydescribed in International Patent Applications PCT/US2017/047217entitled “Illuminating with a Multizone Mixing Cup”, andPCT/US2017/047224 entitled “Illuminating with a Multizone Mixing Cup”,the entirety of which are hereby incorporated by this reference as iffully set forth herein.

In some implementations, the luminescent materials may comprisephosphors comprising one or more of the following materials:BaMg₂Al₁₆O₂₇:Eu²⁺, BaMg₂Al₁₆O₂₇:Eu²⁺,Mn²⁺, CaSiO₃:Pb,Mn, CaWO₄:Pb,MgWO₄, Sr₅Cl(PO₄)₃:Eu²⁺, Sr₂P₂O₇:Sn²⁺, Sr₆P₅BO₂₀:Eu, Ca₅F(PO₄)₃:Sb,(Ba,Ti)₂P₂O₇:Ti, Sr₅F(PO₄)₃:Sb,Mn, (La,Ce,Tb)PO₄:Ce,Tb,(Ca,Zn,Mg)₃(PO₄)₂:Sn, (Sr,Mg)₃(PO₄)₂:Sn, Y₂O₃:Eu³⁺, Mg₄(F)GeO₆:Mn,LaMgAl₁₁O₁₉:Ce, LaPO₄:Ce, SrAl₁₂O₁₉:Ce, BaSi₂O₅:Pb, SrB₄O₇:Eu,Sr₂MgSi₂O₇:Pb, Gd₂O₂S:Tb, Gd₂O₂S:Eu, Gd₂O₂S:Pr, Gd₂O₂S:Pr,Ce,F,Y₂O₂S:Tb, Y₂O₂S:Eu, Y₂O₂S:Pr, Zn(0.5)Cd(0.4)S:Ag, Zn(0.4)Cd(0.6)S:Ag,Y₂SiO₅:Ce, YAlO₃:Ce, Y₃(Al,Ga)₅O₁₂:Ce, CdS:In, ZnO:Ga, ZnO:Zn,(Zn,Cd)S:Cu,Al, ZnCdS:Ag,Cu, ZnS:Ag, ZnS:Cu, NaI:Tl, CsI:Tl,⁶LiF/ZnS:Ag, ⁶LiF/ZnS:Cu,Al,Au, ZnS:Cu,Al, ZnS:Cu,Au,Al, CaAlSiN₃:Eu,(Sr,Ca)AlSiN₃:Eu, (Ba,Ca,Sr,Mg)₂SiO₄:Eu, Lu₃Al₅O₁₂:Ce, Eu³⁺(Gd_(0.9)Y_(0.1))₃Al₅O₁₂:Bi³⁺,Tb³⁺, Y₃Al₅O₁₂:Ce, (La,Y)₃Si₆N₁₁:Ce,Ca₂AlSi₃O₂N₅:Ce³⁺, Ca₂AlSi₃O₂N₅:Eu^(2+,) BaMgAl₁₀O₁₇:Eu, Sr₅(PO₄)₃Cl:Eu,(Ba,Ca,Sr,Mg)₂SiO₄:Eu, Si_(6-z)Al_(z)N_(8-z)O_(z):Eu (wherein 0<z≤4.2);M₃Si₆O₁₂N₂:Eu (wherein M=alkaline earth metal element),(Mg,Ca,Sr,Ba)Si₂O₂N₂:Eu, Sr₄Al₁₄O₂₅:Eu, (Ba,Sr,Ca)Al₂O₄:Eu,(Sr,Ba)Al₂Si₂O₅:Eu, (Ba,Mg)₂SiO₄:Eu, (Ba,Sr,Ca)₂(Mg, Zn)Si₂O₇:Eu,(Ba,Ca,Sr,Mg)₉(Sc,Y,Lu,Gd)₂(Si,Ge)₆O₂₄:Eu, Y₂SiO₅:CeTb,Sr₂P₂O₇—Sr₂B₂O₅:Eu, Sr₂Si₃O₈-2SrCl₂:Eu, Zn₂SiO₄:Mn, CeMgAl₁₁O₁₉:Tb,Y₃Al₅O₁₂:Tb, Ca₂Y₈(SiO₄)₆O₂:Tb, La₃Ga₅SiO₁₄:Tb,(Sr,Ba,Ca)Ga₂S₄:Eu,Tb,Sm, Y₃(Al,Ga)₅O₁₂:Ce,(Y,Ga,Tb,La,Sm,Pr,Lu)₃(Al,Ga)₅O₁₂:Ce, Ca₃Sc₂Si₃O₁₂:Ce,Ca₃(Sc,Mg,Na,Li)₂Si₃O₁₂:Ce, CaSc₂O₄:Ce, Eu-activated 13-Sialon,SrAl₂O₄:Eu, (La,Gd,Y)₂O₂S:Tb, CeLaPO₄:Tb, ZnS:Cu,Al, ZnS:Cu,Au,Al,(Y,Ga,Lu,Sc,La)BO₃:Ce,Tb, Na₂Gd₂B₂O₇:Ce,Tb,(Ba,Sr)₂(Ca,Mg,Zn)B₂O₆:K,Ce,Tb, Ca₈Mg(SiO₄)₄Cl₂:Eu,Mn,(Sr,Ca,Ba)(Al,Ga,In)₂S₄:Eu, (Ca,Sr)₈(Mg,Zn)(SiO₄)₄Cl₂:Eu,Mn,M₃Si₆O₉N₄:Eu, Sr₅Al₅Si₂₁O₂N₃₅:Eu, Sr₃Si₁₃Al₃N₂₁O₂:Eu,(Mg,Ca,Sr,Ba)₂Si₅N₈:Eu, (La,Y)₂O₂S:Eu, (Y,La,Gd,Lu)₂O₂S:Eu, Y(V,P)O₄:Eu,(Ba,Mg)₂SiO₄:Eu,Mn, (Ba,Sr,Ca,Mg)₂SiO₄:Eu,Mn, LiW₂O₅:Eu, LiW₂O₅:Eu,Sm,Eu²W₂O₉, Eu²W₂O₉:Nb and Eu²W₂O₉:Sm, (Ca,Sr)S:Eu, YAlO₃:Eu,Ca₂Y₈(SiO₄)₆O₂:Eu, LiY₉(SiO₄)₆O₂:Eu, (Y,Gd)₃Al₅O₁₂:Ce,(Tb,Gd)₃Al₅O₁₂:Ce, (Mg,Ca,Sr,Ba)₂Si₅(N,O)₈:Eu, (Mg,Ca,Sr,Ba)Si(N,O)₂:Eu,(Mg,Ca,Sr,Ba)AlSi(N,O)₃:Eu, (Sr,Ca,Ba,Mg)₁₀(PO₄)₆Cl₂:Eu,Mn,Eu,Ba₃MgSi₂O₅:Eu,Mn, (Ba,Sr,Ca,Mg)₃(Zn,Mg)Si₂O₈:Eu,Mn,(k-x)MgO.xAF₂.GeO₂:yMn⁴⁺ (wherein k=2.8 to 5, x=0.1 to 0.7, y=0.005 to0.015, A=Ca, Sr, Ba, Zn or a mixture thereof), Eu-activated α-Sialon,(Gd,Y,Lu,La)₂O₃:Eu, Bi, (Gd,Y,Lu,La)₂O₂S:Eu,Bi, (Gd,Y,Lu,La)VO₄:Eu,Bi,SrY₂S₄:Eu,Ce, CaLa₂S₄:Ce,Eu, (Ba,Sr,Ca)MgP₂O₇:Eu, Mn,(Sr,Ca,Ba,Mg,Zn)₂P₂O₇:Eu,Mn, (Y,Lu)₂WO₆:Eu,Ma,(Ba,Sr,Ca)_(x)Si_(y)Nz:Eu,Ce (wherein x, y and z are integers equal toor greater than 1),(Ca,Sr,Ba,Mg)₁₀(PO₄)₆(F,Cl,Br,OH):Eu,Mn,((Y,Lu,Gd,Tb)_(1-x-y)Sc_(x)Ce_(y))₂(Ca,Mg)(Mg,Zn)_(2+r)Si_(z-q)Ge_(q)O_(12+δ),SrAlSi₄N₇, Sr₂Al₂Si₉O₂N₁₄:Eu, M¹ _(a)M² _(b)M³ _(c)O_(d) (whereinM¹=activator element including at least Ce, M²=bivalent metal element,M³=trivalent metal element, 0.0001≤a≤0.2, 0.8≤b≤1.2, 1.6≤c≤2.4 and3.2≤d≤4.8), A_(2+x)M_(y)Mn_(z)F_(n) (wherein A=Na and/or K; M=Si and Al,and −1≤x≤1, 0.9≤y+z≤1.1, 0.001≤z≤0.4 and 5≤n≤7), KSF/KSNAF, or(La_(1-x-y), Eu_(x), Ln_(y))₂O₂S (wherein 0.02≤x≤0.50 and 0≤y≤0.50,Ln=Y³⁺, Gd³⁺, Lu³⁺, Sc³⁺, Sm³⁺ or Er³⁺). In some preferredimplementations, the luminescent materials may comprise phosphorscomprising one or more of the following materials: CaAlSiN₃:Eu,(Sr,Ca)AlSiN₃:Eu, BaMgAl₁₀O₁₇:Eu, (Ba,Ca,Sr,Mg)₂SiO₄:Eu, β-SiAlON,Lu₃Al₅O₁₂:Ce, Eu³⁺ (Cd_(0.9)Y_(0.1))₃Al₅O₁₂:Bi³⁺,Tb^(3+,) Y₃Al₅O₁₂:Ce,La₃Si₆N₁₁:Ce, (La,Y)₃Si₆N₁₁:Ce, Ca₂AlSi₃O₂N₅:Ce³⁺,Ca₂AlSi₃O₂N₅:Ce³⁺,Eu²⁺, Ca₂AlSi₃O₂N₅:Eu^(2+,) BaMgAl₁₀O₁₇:Eu²⁺,Sr_(4.5)Eu_(0.5)(PO₄)₃Cl, or M¹ _(a)M² _(b)M³ _(c)O_(d) (whereinM¹=activator element comprising Ce, M²=bivalent metal element,M³=trivalent metal element, 0.0001≤a≤0.2, 0.8≤b≤1.2, 1.6≤c≤2.4 and3.2≤d≤4.8). In further preferred implementations, the luminescentmaterials may comprise phosphors comprising one or more of the followingmaterials: CaAlSiN₃:Eu, BaMgAl₁₀O₁₇:Eu, Lu₃Al₅O₁₂:Ce, or Y₃Al₅O₁₂:Ce.

Some implementations of the present invention relate to use of solidstate emitter packages. A solid state emitter package typically includesat least one solid state emitter chip that is enclosed with packagingelements to provide environmental and/or mechanical protection, colorselection, and light focusing, as well as electrical leads, contacts ortraces enabling electrical connection to an external circuit.Encapsulant material, optionally including luminophoric material, may bedisposed over solid state emitters in a solid state emitter package.Multiple solid state emitters may be provided in a single package. Apackage including multiple solid state emitters may include at least oneof the following: a single leadframe arranged to conduct power to thesolid state emitters, a single reflector arranged to reflect at least aportion of light emanating from each solid state emitter, a singlesubmount supporting each solid state emitter, and a single lens arrangedto transmit at least a portion of light emanating from each solid stateemitter. Individual LEDs or groups of LEDs in a solid state package(e.g., wired in series) may be separately controlled. As depictedschematically in FIG. 2, multiple solid state packages 200 may bearranged in a single semiconductor light emitting device 100. Individualsolid state emitter packages or groups of solid state emitter packages(e.g., wired in series) may be separately controlled. Separate controlof individual emitters, groups of emitters, individual packages, orgroups of packages, may be provided by independently applying drivecurrents to the relevant components with control elements known to thoseskilled in the art. In one embodiment, at least one control circuit 201a may include a current supply circuit configured to independently applyan on-state drive current to each individual solid state emitter, groupof solid state emitters, individual solid state emitter package, orgroup of solid state emitter packages. Such control may be responsive toa control signal (optionally including at least one sensor 202 arrangedto sense electrical, optical, and/or thermal properties and/orenvironmental conditions), and a control system 203 may be configured toselectively provide one or more control signals to the at least onecurrent supply circuit. In various embodiments, current to differentcircuits or circuit portions may be pre-set, user-defined, or responsiveto one or more inputs or other control parameters. The design andfabrication of semiconductor light emitting devices are well known tothose skilled in the art, and hence further description thereof will beomitted.

FIG. 3 illustrates a 1931 International Commission on Illumination (CIE)chromaticity diagram. The 1931 CIE Chromaticity diagram is atwo-dimensional chromaticity space in which every visible color isrepresented by a point having x- and y-coordinates. Fully saturated(monochromatic) colors appear on the outer edge of the diagram, whileless saturated colors (which represent a combination of wavelengths)appear on the interior of the diagram. The term “saturated”, as usedherein, means having a purity of at least 85%, the term “purity” havinga well-known meaning to persons skilled in the art, and procedures forcalculating purity being well-known to those of skill in the art. ThePlanckian locus, or black body locus (BBL), represented by line 150 onthe diagram, follows the color an incandescent black body would take inthe chromaticity space as the temperature of the black body changes fromabout 1000 K to 10,000 K. The black body locus goes from deep red at lowtemperatures (about 1000 K) through orange, yellowish white, white, andfinally bluish white at very high temperatures. The temperature of ablack body radiator corresponding to a particular color in achromaticity space is referred to as the “correlated color temperature.”In general, light corresponding to a correlated color temperature (CCT)of about 2700 K to about 6500 K is considered to be “white” light. Inparticular, as used herein, “white light” generally refers to lighthaving a chromaticity point that is within a 10-step MacAdam ellipse ofa point on the black body locus having a CCT between 2700 K and 6500 K.However, it will be understood that tighter or looser definitions ofwhite light can be used if desired. For example, white light can referto light having a chromaticity point that is within a seven step MacAdamellipse of a point on the black body locus having a CCT between 2700 Kand 6500 K. The distance from the black body locus can be measured inthe CIE 1960 chromaticity diagram, and is indicated by the symbol Δuv,or DUV. If the chromaticity point is above the Planckian locus the DUVis denoted by a positive number; if the chromaticity point is below thelocus, DUV is indicated with a negative number. If the DUV issufficiently positive, the light source may appear greenish or yellowishat the same CCT. If the DUV is sufficiently negative, the light sourcecan appear to be purple or pinkish at the same CCT. Observers may preferlight above or below the Planckian locus for particular CCT values. DUVcalculation methods are well known by those of ordinary skill in the artand are more fully described in ANSI C78.377, American National Standardfor Electric Lamps-Specifications for the Chromaticity of Solid StateLighting (SSL) Products, which is incorporated by reference herein inits entirety for all purposes. A point representing the CIE StandardIlluminant D65 is also shown on the diagram. The D65 illuminant isintended to represent average daylight and has a CCT of approximately6500 K and the spectral power distribution is described more fully inJoint ISO/CIE Standard, ISO 10526:1999/CIE S005/E-1998, CIE StandardIlluminants for Colorimetry, which is incorporated by reference hereinin its entirety for all purposes.

The light emitted by a light source may be represented by a point on achromaticity diagram, such as the 1931 CIE chromaticity diagram, havingcolor coordinates denoted (ccx, ccy) on the X-Y axes of the diagram. Aregion on a chromaticity diagram may represent light sources havingsimilar chromaticity coordinates.

The ability of a light source to accurately reproduce color inilluminated objects is typically characterized using the color renderingindex (“CRI”), also referred to as the CIE Ra value. The Ra value of alight source is a modified average of the relative measurements of howthe color rendition of an illumination system compares to that of areference black-body radiator or daylight spectrum when illuminatingeight reference colors R1-R8. Thus, the Ra value is a relative measureof the shift in surface color of an object when lit by a particularlamp. The Ra value equals 100 if the color coordinates of a set of testcolors being illuminated by the illumination system are the same as thecoordinates of the same test colors being irradiated by a referencelight source of equivalent CCT. For CCTs less than 5000 K, the referenceilluminants used in the CRI calculation procedure are the SPDs ofblackbody radiators; for CCTs above 5000 K, imaginary SPDs calculatedfrom a mathematical model of daylight are used. These reference sourceswere selected to approximate incandescent lamps and daylight,respectively. Daylight generally has an Ra value of nearly 100,incandescent bulbs have an Ra value of about 95, fluorescent lightingtypically has an Ra value of about 70 to 85, while monochromatic lightsources have an Ra value of essentially zero. Light sources for generalillumination applications with an Ra value of less than 50 are generallyconsidered very poor and are typically only used in applications whereeconomic issues preclude other alternatives. The calculation of CIE Ravalues is described more fully in Commission Internationale del'Éclairage. 1995. Technical Report: Method ofMeasuring and SpecifyingColour Rendering Properties of Light Sources, CIE No. 13.3-1995. Vienna,Austria: Commission Internationale de l'Éclairage, which is incorporatedby reference herein in its entirety for all purposes. In addition to theRa value, a light source can also be evaluated based on a measure of itsability to render a saturated red reference color R9, also known as testcolor sample 9 (“TCS09”), with the R9 color rendering value (“R9value”). Light sources can also be evaluated based on a measure ofability to render additional colors R10-R15, which include realisticcolors like yellow, green, blue, Caucasian skin color (R13), tree leafgreen, and Asian skin color (R15), respectively. Light sources canfurther be evaluated by calculating the gamut area index (“GAI”).Connecting the rendered color points from the determination of the CIERa value in two dimensional space will form a gamut area. Gamut areaindex is calculated by dividing the gamut area formed by the lightsource with the gamut area formed by a reference source using the sameset of colors that are used for CRI. GAI uses an Equal Energy Spectrumas the reference source rather than a black body radiator. A gamut areaindex related to a black body radiator (“GAIBB”) can be calculated byusing the gamut area formed by the blackbody radiator at the equivalentCCT to the light source.

The ability of a light source to accurately reproduce color inilluminated objects can be characterized using the metrics described inIES Method for Evaluating Light Source Color Rendition, IlluminatingEngineering Society, Product ID: TM-30-15 (referred to herein as the“TM-30-15 standard”), which is incorporated by reference herein in itsentirety for all purposes. The TM-30-15 standard describes metricsincluding the Fidelity Index (Rf) and the Gamut Index (Rg) that can becalculated based on the color rendition of a light source for 99 colorevaluation samples (“CES”). The 99 CES provide uniform color spacecoverage, are intended to be spectral sensitivity neutral, and providecolor samples that correspond to a variety of real objects. Rf valuesrange from 0 to 100 and indicate the fidelity with which a light sourcerenders colors as compared with a reference illuminant. Rg valuesprovide a measure of the color gamut that the light source providesrelative to a reference illuminant. The range of Rg depends upon the Rfvalue of the light source being tested. The reference illuminant isselected depending on the CCT. For CCT values less than or equal to 4500K, Planckian radiation is used. For CCT values greater than or equal to5500 K, CIE Daylight illuminant is used. Between 4500 K and 5500 K aproportional mix of Planckian radiation and the CIE Daylight illuminantis used, according to the following equation:

${{S_{r,M}\left( {\lambda,T_{t}} \right)} = {{\frac{5500 - T_{t}}{1000}{S_{r,P}\left( {\lambda,T_{t}} \right)}} + {\left( {1 - \frac{5500 - T_{t}}{1000}} \right){S_{r,D}\left( {\lambda,T_{t}} \right)}}}},$

where T_(t) is the CCT value, S_(τ,M)(λ,T_(t)) is the proportional mixreference illuminant, S_(τ,P)(λ,T_(t)) is Planckian radiation, andS_(τ,D)(λ,T_(t)) is the CIE Daylight illuminant.

The ability of a light source to provide illumination that allows forthe clinical observation of cyanosis is based upon the light source'sspectral power density in the red portion of the visible spectrum,particularly around 660 nm. The cyanosis observation index (“COI”) isdefined by AS/NZS 1680.2.5 Interior Lighting Part 2.5: Hospital andMedical Tasks, Standards Australia, 1997 which is incorporated byreference herein in its entirety, including all appendices, for allpurposes. COI is applicable for CCTs from about 3300 K to about 5500 K,and is preferably of a value less than about 3.3. If a light source'soutput around 660 nm is too low a patient's skin color may appear darkerand may be falsely diagnosed as cyanosed. If a light source's output at660 nm is too high, it may mask any cyanosis, and it may not bediagnosed when it is present. COI is a dimensionless number and iscalculated from the spectral power distribution of the light source. TheCOI value is calculated by calculating the color difference betweenblood viewed under the test light source and viewed under the referencelamp (a 4000 K Planckian source) for 50% and 100% oxygen saturation andaveraging the results. The lower the value of COI, the smaller the shiftin color appearance results under illumination by the source underconsideration.

Circadian illuminance (CLA) is a measure of circadian effective light,spectral irradiance distribution of the light incident at the corneaweighted to reflect the spectral sensitivity of the human circadiansystem as measured by acute melatonin suppression after a one-hourexposure, and CS, which is the effectiveness of the spectrally weightedirradiance at the cornea from threshold (CS=0.1) to saturation (CS=0.7).The values of CLA are scaled such that an incandescent source at 2856 K(known as CIE Illuminant A) which produces 1000 lux (visual lux) willproduce 1000 units of circadian lux (CLA). CS values are transformed CLAvalues and correspond to relative melotonian suppression after one hourof light exposure for a 2.3 mm diameter pupil during the mid-point ofmelotonian production. CS is calculated from

${CS} = \left| {0.7{\left( {1 - \frac{1}{1 + \left( \frac{CLA}{355.7} \right)^{\hat{}1.126}}} \right).}} \right.$

The calculation of CLA is more fully described in Rea et al., “Modellingthe spectral sensitivity of the human circadian system,” LightingResearch and Technology, 2011; 0: 1-12, and Figueiro et al., “Designingwith Circadian Stimulus”, October 2016, LD+A Magazine, IlluminatingEngineering Society of North America, which are incorporated byreference herein in its entirety for all purposes. Figueiro et al.describe that exposure to a CS of 0.3 or greater at the eye, for atleast one hour in the early part of the day, is effective forstimulating the circadian system and is associated with better sleep andimproved behavior and mood.

In some aspects the present disclosure relates to lighting devices andmethods to provide light having particular vision energy and circadianenergy performance. Many figures of merit are known in the art, some ofwhich are described in Ji Hye Oh, Su Ji Yang and Young Rag Do, “Healthy,natural, efficient and tunable lighting: four-package white LEDs foroptimizing the circadian effect, color quality and vision performance,”Light: Science & Applications (2014) 3: e141-e149, which is incorporatedherein in its entirety, including supplementary information, for allpurposes. Luminous efficacy of radiation (“LER”) can be calculated fromthe ratio of the luminous flux to the radiant flux (S(λ)), i.e. thespectral power distribution of the light source being evaluated, withthe following equation:

${L\; E\; {R\left( \frac{lm}{W} \right)}} = {683\left( \frac{lm}{W} \right){\frac{\int{{V(\lambda)}{S(\lambda)}d\; \lambda}}{\int{{S(\lambda)}d\; \lambda}}.}}$

Circadian efficacy of radiation (“CER”) can be calculated from the ratioof circadian luminous flux to the radiant flux, with the followingequation:

${{CER}\left( \frac{blm}{W} \right)} = {683\left( \frac{blm}{W} \right){\frac{\int{{C(\lambda)}{S(\lambda)}d\; \lambda}}{\int{{S(\lambda)}d\; \lambda}}.}}$

Circadian action factor (“CAF”) can be defined by the ratio of CER toLER, with the following equation:

$\left( \frac{blm}{lm} \right) = {\frac{{CER}\left( \frac{blm}{W} \right)}{{LER}\left( \frac{lm}{W} \right)}.}$

The term “blm” refers to biolumens, units for measuring circadian flux,also known as circadian lumens. The term “lm” refers to visual lumens.V(λ) is the photopic spectral luminous efficiency function and C(λ) isthe circadian spectral sensitivity function. The calculations herein usethe circadian spectral sensitivity function, C(λ), from Gall et al.,Proceedings of the CIE Symposium 2004 on Light and Health: Non-VisualEffects, 30 September-2 Oct. 2004; Vienna, Austria 2004. CIE: Wien,2004, pp 129-132, which is incorporated herein in its entirety for allpurposes. By integrating the amount of light (milliwatts) within thecircadian spectral sensitivity function and dividing such value by thenumber of photopic lumens, a relative measure of melatonin suppressioneffects of a particular light source can be obtained. A scaled relativemeasure denoted as melatonin suppressing milliwatts per hundred lumensmay be obtained by dividing the photopic lumens by 100. The term“melatonin suppressing milliwatts per hundred lumens” consistent withthe foregoing calculation method is used throughout this application andthe accompanying figures and tables.

In some exemplary implementations, the present disclosure providessemiconductor light emitting devices 100 that include a plurality of LEDstrings, with each LED string having a recipient luminophoric mediumthat comprises a luminescent material. The LED(s) in each string and theluminophoric medium in each string together emit an unsaturated lighthaving a color point within a color range in the 1931 CIE chromaticitydiagram. A “color range” in the 1931 CIE chromaticity diagram refers toa bounded area defining a group of color coordinates (ccx, ccy).

In some implementations, three LED strings (101A/101B/101C) are presentin a device 100, and the LED strings can have recipient luminophoricmediums (102A/102B/102C). A first LED string 101A and a firstluminophoric medium 102A together can emit a first light having a firstcolor point within a white color range. The combination of the first LEDstring 101A and the first luminophoric medium 102A are also referred toherein as a “white channel.” A second LED string 101B and a secondluminophoric medium 102B together can emit a second light having asecond color point within a red color range. The combination of thesecond LED string 101B and the second luminophoric medium 102B are alsoreferred to herein as a “red channel.” A third LED string 101C and athird luminophoric medium 102C together can emit a third light having athird color point within a cyan color range. The combination of thethird LED string 101C and the third luminophoric medium 102C are alsoreferred to herein as a “cyan channel.” The first, second, and third LEDstrings 101A/101B/101C can be provided with independently appliedon-state drive currents in order to tune the intensity of the first,second, and third unsaturated light produced by each string andluminophoric medium together. By varying the drive currents in acontrolled manner, the color coordinate (ccx, ccy) of the total lightthat is emitted from the device 100 can be tuned. In someimplementations, white light can be generated in modes that only producelight from one or two of the LED strings. In one implementation, whitelight is generated using only the first and second LED strings, i.e. thewhite and red channels. In another implementation, white light isgenerated using only the first and third LED strings, i.e., the whiteand cyan channels. In some implementations, only one of the LED strings,the white channel, is producing light during the generation of whitelight, as the other two LED strings are not necessary to generate whitelight at the desired color point with the desired color renderingperformance. Some aspects of some suitable white channel components andred channel components have been described in International PatentApplication Nos. PCT/US2017/047230, PCT/US2017/047231, andPCT/US2017/047233 filed Aug. 16, 2017, the entireties of which areincorporated herein for all purposes.

FIG. 4 depicts suitable color ranges for some implementations of thedisclosure. FIG. 4 depicts a cyan color range 303A defined by a lineconnecting the ccx, ccy color coordinates (0.18, 0.55) and (0.27, 0.72),the constant CCT line of 9000 K, the Planckian locus between 9000 K and1800 K, the constant CCT line of 1800 K, and the spectral locus. FIG. 4depicts a red color range 302A defined by the spectral locus between theconstant CCT line of 1600 K and the line of purples, the line ofpurples, a line connecting the ccx, ccy color coordinates (0.61, 0.21)and (0.47, 0.28), and the constant CCT line of 1600 K. It should beunderstood that any gaps or openings in the described boundaries for thecolor ranges 302A and 303A should be closed with straight lines toconnect adjacent endpoints in order to define a closed boundary for eachcolor range.

In some implementations, suitable color ranges can be narrower thanthose depicted in FIG. 4. FIG. 5 depicts some suitable color ranges forsome implementations of the disclosure. A red color range 302B can bedefined by a 20-step MacAdam ellipse at a CCT of 1200 K, 20 points belowthe Planckian locus. A cyan color range 303B can be defined by theregion bounded by lines connecting (0.360, 0.495), (0.371, 0.518),(0.388, 0.522), and (0.377, 0.499). FIG. 6 depicts some further colorranges suitable for some implementations of the disclosure. A red colorrange 302C is defined by a polygonal region on the 1931 CIE ChromaticityDiagram defined by the following ccx, ccy color coordinates: (0.53,0.41), (0.59, 0.39), (0.63, 0.29), (0.58, 0.30). A cyan color range 303Cis defined by a line connecting the ccx, ccy color coordinates (0.18,0.55) and (0.27, 0.72), the constant CCT line of 9000 K, the Planckianlocus between 9000 K and 4600 K, the constant CCT line of 4600 K, andthe spectral locus. A cyan color range 303D is defined by the constantCCT line of 4600 K, the spectral locus, the constant CCT line of 1800 K,and the Planckian locus between 4600 K and 1800 K.

The LEDs in the white channel can produce color points within acceptablecolor ranges 304A, 402, 304B, and 304C. White color range 304A can bedefined by a polygonal region on the 1931 CIE Chromaticity Diagramdefined by the following ccx, ccy color coordinates: (0.4006, 0.4044),(0.3736, 0.3874), (0.3670, 0.3578), (0.3898, 0.3716), which correlatesto an ANSI C78.377-2008 standard 4000 K nominal CCT white light withtarget CCT and tolerance of 3985±275 K and target duv and tolerance of0.001±0.006, as more fully described in American National Standard ANSIC78.377-2008, “Specifications for the Chromaticity of Solid StateLighting Products,” National Electrical Manufacturers Association,American National Standard Lighting Group, which is incorporated hereinin its entirety for all purposes. In some implementations, suitablewhite color ranges can be described as MacAdam ellipse color ranges inthe 1931 CIE Chromaticity Diagram color space, as illustratedschematically in FIG. 7, which depicts a color range 402, the black bodylocus 401, and a line 403 of constant ccy coordinates on the 1931 CIEChromaticity Diagram. In FIG. 7, MacAdam ellipse ranges are describedwith major axis “a”, minor axis “b”, and ellipse rotation angle θrelative to line 403. In some implementations, the white color range canbe range 304B, an embodiment of color range 402, and can be defined as asingle 5-step MacAdam ellipse with center point (0.3818, 0.3797) with amajor axis “a” of 0.01565, minor axis “b” of 0.00670, with an ellipserotation angle θ of 52.70°, shown relative to a line 403. In someimplementations, the white color range can be range 304C, an embodimentof color range 402, and can be defined as a single 3-step MacAdamellipse with center point (0.3818, 0.3797) with a major axis “a” of0.00939, minor axis “b” of 0.00402, with an ellipse rotation angle θ of53.7°, shown relative to a line 403. FIG. 9 depicts a normalizedspectral power distribution for a suitable white channel phosphor-coatedLED, which can be LUXEON Z model LXZ1-4080, a 4000 K nominal CCT 80 CRILED. In other implementations, the white channel can comprise othercommercial white LEDs with CCT values between about 3500 K and about6500 K.

In some implementations, the LEDs in the first, second and third LEDstrings can be LEDs with peak emission wavelengths at or below about 535nm. In some implementations, the LEDs emit light with peak emissionwavelengths between about 360 nm and about 535 nm. In someimplementations, the LEDs in the first, second and third LED strings canbe formed from InGaN semiconductor materials. In some preferredimplementations, the first, second, and third LED strings can have LEDshaving a peak wavelength between about 405 nm and about 485 nm. In someimplementations, the third LED string can have LEDs having a peakwavelength between about 440 nm and about 465 nm. The LEDs used in thefirst, second and third LED strings may have full-width half-maximumwavelength ranges of between about 10 nm and about 30 nm. In somepreferred implementations, the first, second, and third LED strings caninclude one or more LUXEON Z Color Line royal blue LEDs (product codeLXZ1-PR01) of color bin codes 3, 4, 5, or 6 or one or more LUXEON ZColor Line blue LEDs (LXZ1-PB01) of color bin code 1 or 2 (LumiledsHolding B.V., Amsterdam, Netherlands). In certain preferredimplementations, the third LED string can include one or more LUXEONroyal blue LEDs (product code LXML-PR01 and LXML-PR02) of color bins 3,4, 5, or 6. The wavelength information for these color bins is providedin Table 1. Similar LEDs from other manufacturers such as OSRAM GmbH andCree, Inc. could also be used, provided they have peak emission andfull-width half-maximum wavelengths of the appropriate values.

TABLE 1 Dominant/Peak Wavelength (nm) Part Number Bin Minimum MaximumLXZ1-PB01 1 460 465 2 465 470 5 480 485 LXZ1-PR01 3 440 445 LXML-PR01 4445 450 LXML-PR02 5 450 455 6 455 460

In implementations utilizing LEDs that emit substantially saturatedlight at wavelengths between about 360 nm and about 535 nm, the device100 can include suitable recipient luminophoric mediums for each LED inorder to produce light having color points within the suitable red colorranges 302A-C, cyan color ranges 303A-D, and white color ranges 304A-Cdescribed herein. The light emitted by each LED string, i.e., the lightemitted from the LED(s) and associated recipient luminophoric mediumtogether, can have a spectral power distribution (“SPD”) having spectralpower with ratios of power across the visible wavelength spectrum fromabout 380 nm to about 780 nm. While not wishing to be bound by anyparticular theory, it is speculated that the use of such LEDs incombination with recipient luminophoric mediums to create unsaturatedlight within the suitable color ranges 302A-C, 303A-D, and 304A-Cprovides for improved color rendering performance for white light acrossa predetermined range of CCTs from a single device 100. Some suitableranges for spectral power distribution ratios of the light emitted bythe LED strings (101B/101C) and recipient luminophoric mediums(102B/102C) together in the red and cyan channels are shown in Table 2.The table shows the ratios of spectral power within wavelength ranges,with an arbitrary reference wavelength range selected for each colorrange and normalized to a value of 100.0. Table 2 also shows suitableminimum and maximum values for the spectral intensities within variousranges relative to the normalized range with a value of 100.0, for thecolor points within the cyan and red color ranges. While not wishing tobe bound by any particular theory, it is speculated that because thespectral power distributions for generated light with color pointswithin the cyan and red color ranges contains higher spectral intensityacross visible wavelengths as compared to lighting apparatuses andmethods that utilize more saturated colors, this allows for improvedcolor rendering for test colors other than R1-R8. In someimplementations, the red channel can have a spectral power distributionwith spectral power in one or more of the wavelength ranges other thanthe arbitrary reference wavelength range increased or decreased within30% greater or less, within 20% greater or less, within 10% greater orless, or within 5% greater or less than the values of a red channelshown in Table 2. In some implementations, the cyan channel can have aspectral power distribution with spectral power in one or more of thewavelength ranges other than the arbitrary reference wavelength rangeincreased or decreased within 30% greater or less, within 20% greater orless, within 10% greater or less, or within 5% greater or less than thevalues of the cyan channel shown in Table 2.

TABLE 2 Relative Spectral Power Distribution in 380-780 nm wavelengthbins Combined color 380 < 420 < 460 < 500 < 540 < 580 < 620 < 660 < 700< 740 < point λ ≤ λ ≤ λ ≤ λ ≤ λ ≤ λ ≤ λ ≤ λ ≤ λ ≤ λ ≤ Channel (ccx, ccy)420 460 500 540 580 620 660 700 740 780 Red 1 (0.5842, 0.3112) 0.0 9.62.0 1.4 9.0 48.5 100.0 73.1 29.5 9.0 Red 2 (0.5842, 0.3112) 0.0 157.82.0 1.4 9.0 48.5 100.0 73.1 29.5 9.0 Red 3 (0.5702, 0.3869) 0.7 2.1 4.112.2 20.5 51.8 100.0 74.3 29.3 8.4 Red 4 (0.5563, 0.3072) 14.8 10.5 6.78.7 8.7 102.8 100.0 11.0 1.5 1.1 Red 5 (0.5941, 0.3215) 0.2 8.5 3.0 5.59.5 60.7 100.0 1.8 0.5 0.3 Red 6 (0.5842, 0.3112) 0.7 2.1 4.1 12.2 20.551.8 100.0 74.3 29.3 8.4 Red 7 (0.5735, 0.3007) 0.0 2.3 5.0 10.2 24.761.0 100.0 71.7 27.8 8.4 Red 8 (0.5700, 0.3870) 0.1 2.7 4.3 9.5 24.660.4 100.0 51.5 12.4 2.4 Red 9 (0.5932, 0.3903) 0.2 1.4 0.7 7.3 22.359.8 100.0 61.2 18.1 4.9 Red 0.0 2.1 2.0 1.4 8.7 48.5 100.0 1.8 0.5 0.3Minimum Red 14.8 157.8 6.7 12.2 24.7 102.8 100.0 74.3 29.5 9.0 MaximumCyan 1 (0.3730, 0.4978) 0.72 15.92 33.52 98.19 100.00 68.55 47.06 22.126.30 1.65 Cyan Range 1 3.9 100.0 112.7 306.2 395.1 318.2 245.0 138.839.5 10.3 Minimum Cyan Range 1 130.6 100.0 553.9 5472.8 9637.9 12476.913285.5 6324.7 1620.3 344.7 Maximum Cyan Range 2 3.9 100.0 112.7 306.2395.1 318.2 245.0 138.8 39.5 10.3 Minimum Cyan Range 2 130.6 100.0 553.92660.6 4361.9 3708.8 2223.8 712.2 285.6 99.6 Maximum

Blends of luminescent materials can be used in luminophoric mediums(102A/102B/102C) to create luminophoric mediums having the desiredsaturated color points when excited by their respective LED strings(101A/101B/101C) including luminescent materials such as those disclosedin co-pending applications PCT/US2016/015318 filed Jan. 28, 2016,entitled “Compositions for LED Light Conversions”, and PCT/US2016/015473filed Jan. 28, 2016, entitled “Illuminating with a Multizone MixingCup”, the entirety of which are hereby incorporated by this reference asif fully set forth herein. Traditionally, a desired combined outputlight can be generated along a tie line between the LED string outputlight color point and the saturated color point of the associatedrecipient luminophoric medium by utilizing different ratios of totalluminescent material to the encapsulant material in which it isincorporated. Increasing the amount of luminescent material in theoptical path will shift the output light color point towards thesaturated color point of the luminophoric medium. In some instances, thedesired saturated color point of a recipient luminophoric medium can beachieved by blending two or more luminescent materials in a ratio. Theappropriate ratio to achieve the desired saturated color point can bedetermined via methods known in the art. Generally speaking, any blendof luminescent materials can be treated as if it were a singleluminescent material, thus the ratio of luminescent materials in theblend can be adjusted to continue to meet a target CIE value for LEDstrings having different peak emission wavelengths. Luminescentmaterials can be tuned for the desired excitation in response to theselected LEDs used in the LED strings (101A/101B/101C), which may havedifferent peak emission wavelengths within the range of from about 360nm to about 535 nm. Suitable methods for tuning the response ofluminescent materials are known in the art and may include altering theconcentrations of dopants within a phosphor, for example.

In some implementations of the present disclosure, luminophoric mediumscan be provided with combinations of two types of luminescent materials.The first type of luminescent material emits light at a peak emissionbetween about 515 nm and about 590 nm in response to the associated LEDstring emission. The second type of luminescent material emits at a peakemission between about 590 nm and about 700 nm in response to theassociated LED string emission. In some instances, the luminophoricmediums disclosed herein can be formed from a combination of at leastone luminescent material of the first and second types described in thisparagraph. In implementations, the luminescent materials of the firsttype can emit light at a peak emission at about 515 nm, 525 nm, 530 nm,535 nm, 540 nm, 545 nm, 550 nm, 555 nm, 560 nm, 565 nm, 570 nm, 575 nm,580 nm, 585 nm, or 590 nm in response to the associated LED stringemission. In preferred implementations, the luminescent materials of thefirst type can emit light at a peak emission between about 520 nm toabout 555 nm. In implementations, the luminescent materials of thesecond type can emit light at a peak emission at about 590 nm, about 595nm, 600 nm, 605 nm, 610 nm, 615 nm, 620 nm, 625 nm, 630 nm, 635 nm, 640nm, 645 nm, 650 nm, 655 nm, 670 nm, 675 nm, 680 nm, 685 nm, 690 nm, 695nm, or 700 nm in response to the associated LED string emission. Inpreferred implementations, the luminescent materials of the first typecan emit light at a peak emission between about 600 nm to about 670 nm.

Some exemplary luminescent materials of the first and second type aredisclosed elsewhere herein and referred to as Compositions A-F. Table 3shows aspects of some exemplar luminescent materials and properties:

TABLE 3 Exemplary Embodiment Suitable Ranges Emission Emission FWHMDensity Peak FWHM Peak Range Range Designator Exemplary Material(s)(g/mL) (nm) (nm) (nm) (nm) Composition Luag: Cerium doped  6.73 535 95530-540  90-100 “A” lutetium aluminum garnet (Lu₃Al₅O₁₂) CompositionYag: Cerium doped yttrium 4.7 550 110 545-555 105-115 “B” aluminumgarnet (Y₃Al₅O₁₂) Composition a 650 nm-peak wavelength 3.1 650 90645-655 85-95 “C” emission phosphor: Europium doped calcium aluminumsilica nitride (CaAlSiN₃) Composition a 525 nm-peak wavelength 3.1 52560 520-530 55-65 “D” emission phosphor: GBAM: BaMgAl₁₀O₁₇: EuComposition a 630 nm-peak wavelength 5.1 630 40 625-635 35-45 “E”emission quantum dot: any semiconductor quantum dot material ofappropriate size for desired emission wavelengths Composition a 610nm-peak wavelength 5.1 610 40 605-615 35-45 “F” emission quantum dot:any semiconductor quantum dot material of appropriate size for desiredemission wavelengths Matrix “M” Silicone binder 1.1 mg/ mm³

Blends of Compositions A-F can be used in luminophoric mediums(102A/102B/102C) to create luminophoric mediums having the desiredsaturated color points when excited by their respective LED strings(101A/101B/101C). In some implementations, one or more blends of one ormore of Compositions A-F can be used to produce luminophoric mediums(102A/102B/102C). In some preferred implementations, one or more ofCompositions A, B, and D and one or more of Compositions C, E, and F canbe combined to produce luminophoric mediums (102A/102B/102C). In somepreferred implementations, the encapsulant for luminophoric mediums(102A/102B/102C) comprises a matrix material having density of about 1.1mg/mm³ and refractive index of about 1.545 or from about 1.4 to about1.6. In some implementations, Composition A can have a refractive indexof about 1.82 and a particle size from about 18 micrometers to about 40micrometers. In some implementations, Composition B can have arefractive index of about 1.84 and a particle size from about 13micrometers to about 30 micrometers. In some implementations,Composition C can have a refractive index of about 1.8 and a particlesize from about 10 micrometers to about 15 micrometers. In someimplementations, Composition D can have a refractive index of about 1.8and a particle size from about 10 micrometers to about 15 micrometers.Suitable phosphor materials for Compositions A, B, C, and D arecommercially available from phosphor manufacturers such as MitsubishiChemical Holdings Corporation (Tokyo, Japan), Intematix Corporation(Fremont, Calif.), EMD Performance Materials of Merck KGaA (Darmstadt,Germany), and PhosphorTech Corporation (Kennesaw, Ga.). In someimplementations, a set of suitable materials for Compositions A-F andMatrix M can be selected, as shown in Table 4 as “Model 1”. In otherimplementations, a set of suitable materials for Compositions A-F andMatrix M can be selected, as shown in Table 4 as “Model 2.”

TABLE 4 Model 1 Model 2 particle re- par- re- Des- Exemplary sizefractive ticle fractive ignator Material(s) (d50) index size indexCompo- Luag: Cerium doped 18.0 μm 1.84  40 μm 1.8 sition “A” lutetiumaluminum garnet (Lu₃Al₅O₁₂) Compo- Yag: Cerium doped 13.5 μm 1.82  30 μm1.85 sition “B” yttrium aluminum garnet (Y₃Al₅O₁₂) Compo- a 650 nm-peak15.0 μm 1.8  10 μm 1.8 sition “C” wavelength emission phosphor: Europiumdoped calcium aluminum silica nitride (CaAlSiN₃) Compo- a 525 nm-peak15.0 μm 1.8  n/a n/a sition “D” wavelength emission phosphor: GBAM:BaMgAl₁₀O₁₇:Eu Compo- a 630 nm-peak 10.0 nm 1.8  n/a n/a sition “E”wavelength emission quantum dot: any semiconductor quantum dot materialof appropriate size for desired emission wavelengths Compo- a 610nm-peak 10.0 nm 1.8  n/a n/a sition “F” wavelength emission quantum dot:any semiconductor quantum dot material of appropriate size for desiredemission wavelengths Matrix Silicone binder 1.545 1.545 “M”

In some aspects, the present disclosure provides semiconductor lightemitting devices 100 that can have a plurality of light emitting diode(LED) strings. Each LED string can have one, or more than one, LED. Asdepicted schematically in FIG. 8, the device 100 may comprise one ormore LED strings (101A/101B/101C) that emit light (schematically shownwith arrows) as in the device depicted in FIG. 1, with each LED stringhaving a recipient luminophoric medium (102A/102B/102C) associatedtherewith, and the light emitted from the LED strings, combined withlight emitted from the recipient luminophoric mediums, passed throughone or more optical elements 103. The device 100 depicted in FIG. 8differs from FIG. 1 in that an additional LED string 101D, having arecipient luminophoric medium 102D, is also present in the device 100.LED string 101D and luminophoric medium 102D can be a duplicate of oneof LED strings 101A/101B/101C with mediums 102A/102B/102C. In someimplementations, the device 100 depicted in FIG. 8 can have two whitechannels, one red channel, and one cyan channel. In otherimplementations, the device 100 depicted in FIG. 8 can have one whitechannel, two red channels, and one cyan channel. In yet otherimplementations, the device 100 depicted in FIG. 8 can have one whitechannel, one red channel, and two cyan channels.

In some aspects, the present disclosure provides semiconductor lightemitting devices capable to producing tunable white light through arange of CCT values. In some implementations, devices can output whitelight at color points along a predetermined path within a 7-step MacAdamellipse around any point on the black body locus having a correlatedcolor temperature between about 1800 K and about 3200 K. In furtherimplementations, devices can output white light at color points along apredetermined path shifted −7±2 DUV from the black body locus having acorrelated color temperature between about 1800 K and about 3200 K. Insome implementations, the devices can generate white light correspondingto a plurality of points along a predefined path with the lightgenerated at each point having light with one or more of Ra greater thanor equal to about 90, R9 greater than or equal to about 55, and GAIBBgreater than or equal to about 95. In some preferred implementations,the devices of the present disclosure can generate white light so thatit falls within a 7-step MacAdam ellipse around any point on the blackbody locus having a correlated color temperature between about 1800 Kand about 3000 K, and generate the fifth unsaturated light correspondingto a plurality of points along a predefined path with the lightgenerated at each point having light with one or more of Ra greater thanor equal to about 90, R9 greater than or equal to about 75, and GAIBBgreater than or equal to about 95. In some implementations the devicesof the present disclosure comprise a drive circuit is configured toadjust the fourth color point so that it falls within a 7-step MacAdamellipse around any point on the black body locus having a correlatedcolor temperature between about 1800 K and about 3200 K, and in some ofthese implementations the light emitting devices are configured togenerate the fourth unsaturated light corresponding to a plurality ofpoints along a predefined path with the light generated at each pointhaving light with one or more of Ra greater than or equal to about 90and R9 greater than or equal to about 55, one or more of Rf greater thanor equal to 75, Rf greater than or equal to about 80, Rf greater than orequal to about 90, Rf greater than about 95, Rf equal to about 100, Rggreater than or equal to about 80 and less than or equal to about 120,Rg greater than or equal to about 90 and less than or equal to about110, Rg greater than or equal to about 95 and less than or equal toabout 105, or Rg equal to about 100. In some implementations the devicescomprise a drive circuit configured to adjust the fourth color point sothat it falls within a 7-step MacAdam ellipse around any point on theblack body locus having a correlated color temperature between about1800 K and about 3000 K, and the light emitting devices are configuredto generate the fourth unsaturated light corresponding to a plurality ofpoints along a predefined path with the light generated at each pointhaving light with one or more of Ra greater than or equal to about 90and R9 greater than or equal to about 60. In some implementations thedevices comprise a drive circuit configured to adjust the fourth colorpoint so that it falls within a 7-step MacAdam ellipse around any pointon the black body locus having a correlated color temperature betweenabout 2000 K and about 3200 K, and the light emitting devices areconfigured to generate the fourth unsaturated light corresponding to aplurality of points along a predefined path with the light generated ateach point having light with one or more of Rf greater than or equal toabout 80, Rf greater than or equal to about 90, Rf greater than about95, Rf equal to about 100, Rg greater than or equal to about 80 and lessthan or equal to about 120, Rg greater than or equal to about 85 andless than or equal to about 115; Rg greater than or equal to about 90and less than or equal to about 110, Rg greater than or equal to about95 and less than or equal to about 105, or Rg equal to about 100. Infurther implementations the devices comprise a drive circuit configuredto adjust the fourth color point so that it falls within a 7-stepMacAdam ellipse around any point on the black body locus having acorrelated color temperature between about 1800 K and about 3200 K, andthe light emitting devices are configured to generate the fourthunsaturated light corresponding to a plurality of points along apredefined path, with the light generated at points along about 85% ofthe predefined path has Ra greater than or equal to about 90, the lightgenerated at points along about 85% of the predefined path has R9greater than or equal to about 65, or both.

EXAMPLES General Simulation Method.

Devices having a plurality of LED strings with particular color pointswere simulated. For each device, LED strings and recipient luminophoricmediums with particular emissions were selected, and then white lightrendering capabilities were calculated for a select number ofrepresentative points on or near the Planckian locus between about 1800K and about 3200 K. Ra, R9, R13, R15, LER, Rf, Rg, CLA, and CSperformance values were calculated at each representative point, and COIvalues were calculated for representative points near the CCT range ofabout 3200 K.

The calculations were performed with Scilab (Scilab Enterprises,Versailles, France), LightTools (Synopsis, Inc., Mountain View, Calif.),and custom software created using Python (Python Software Foundation,Beaverton, Oreg.). Each LED string was simulated with an LED emissionspectrum and excitation and emission spectra of luminophoric medium(s).For luminophoric mediums comprising phosphors, the simulations alsoincluded the absorption spectrum and particle size of phosphorparticles. The LED strings generating combined emissions within white,red, and cyan color regions were prepared using spectra of a LUXEON ZColor Line royal blue LED (product code LXZ1-PR01) of color bin codes 3,4, 5, or 6, a LUXEON Z Color Line blue LED (LXZ1-PB01) of color bin code1 or 2, and LUXEON Rebel Royal Blue LED (product code LXML-PR01 orLXML-PR02) of color bin code 3, 4, 5, or 6 (Lumileds Holding B.V.,Amsterdam, Netherlands). Similar LEDs from other manufacturers such asOSRAM GmbH and Cree, Inc. could also be used.

The emission, excitation and absorption curves are available fromcommercially available phosphor manufacturers such as MitsubishiChemical Holdings Corporation (Tokyo, Japan), Intematix Corporation(Fremont, Calif.), EMD Performance Materials of Merck KGaA (Darmstadt,Germany), and PhosphorTech Corporation (Kennesaw, Ga.). The luminophoricmediums used in the LED strings were combinations of one or more ofCompositions A, B, and D and one or more of Compositions C, E, and F asdescribed more fully elsewhere herein. Those of skill in the artappreciate that various combinations of LEDs and luminescent blends canbe combined to generate combined emissions with desired color points onthe 1931 CIE chromaticity diagram and the desired spectral powerdistributions.

Example 1

A semiconductor light emitting device was simulated having three LEDstrings. A first LED string is driven by a blue LED having peak emissionwavelength of approximately 450 nm to approximately 455 nm, utilizes arecipient luminophoric medium, and generates a combined emission of awhite color point of (0.3818, 0.3797). A second LED string is driven bya blue LED having peak emission wavelength of approximately 450 nm toapproximately 455 nm, utilizes a recipient luminophoric medium, andgenerates a combined emission of a red color point with a 1931 CIEchromaticity diagram color point of (0.5932, 0.3903). A third LED stringis driven by a blue LED having peak emission wavelength of approximately450 nm to approximately 455 nm, utilizes a recipient luminophoricmedium, and generates a combined emission of a cyan color point with a1931 CIE chromaticity diagram color point of (0.373, 0.4978).

Tables 5 and 6 below shows the spectral power distributions for the redand cyan color points generated by the device of this Example, withspectral power shown within wavelength ranges in nanometers from 380 nmto 780 nm, with an arbitrary reference wavelength range selected foreach color range and normalized to a value of 100.0. Table 7 showscolor-rendering and circadian performance characteristics of the devicefor a representative selection of white light color points near thePlanckian locus.

TABLE 5 380 < 420 < 460 < 500 < 540 < 580 < 620 < 660 < 700 < 740 < λ ≤420 λ ≤ 460 λ ≤ 500 λ ≤ 540 λ ≤ 580 λ ≤ 620 λ ≤ 660 λ ≤ 700 λ ≤ 740 λ ≤780 Red 0.2 1.4 0.7 7.3 22.3 59.8 100.0 61.2 18.1 4.9 Cyan 0.7 15.9 33.598.2 100.0 68.6 47.1 22.1 6.3 1.7

TABLE 6 380 < 400 < 420 < 440 < 460 < 480 < 500 < 520 < 540 < 560 < 580< λ ≤ 400 λ ≤ 420 λ ≤ 440 λ ≤ 460 λ ≤ 480 λ ≤ 500 λ ≤ 520 λ ≤ 540 λ ≤560 λ ≤ 580 λ ≤ 600 Red 0.0 0.3 1.4 1.3 0.4 0.9 4.2 9.4 15.3 26.4 45.8Cyan 0.2 1.2 8.1 22.2 17.5 46.3 88.2 98.5 100.0 90.2 73.4 600 < 620 <640 < 660 < 680 < 700 < 720 < 740 < 760 < 780 < λ ≤ 620 λ ≤ 640 λ ≤ 660λ ≤ 680 λ ≤ 700 λ ≤ 720 λ ≤ 740 λ ≤ 760 λ ≤ 780 λ ≤ 800 Red 66.0 87.0100.0 72.5 42.0 22.3 11.6 6.1 3.1 0.0 Cyan 57.0 48.1 41.4 27.0 15.1 7.94.0 2.1 1.0 0.0 White Cyan Red Channel Channel Channel Relative RelativeRelative CCT duv Intensity Intensity Intensity Ra R9 ccx ccy Rf Rg COIR13 R15 LER CLA CS 3200 0.53 0.57 0.22 0.21 89.9 59.6 0.424 0.4005 88102 2.42 90.1 87.3 296.5 1007 0.531 3102 0.31 0.52 0.24 0.24 90.8 63.80.4303 0.4024 89 102 2.82 91.2 88.6 292.8 977 0.527 3001 −0.04 0.47 0.260.27 91.7 67.7 0.4368 0.4039 89 102 3.42 92.2 89.9 288.9 946 0.522 29030.39 0.42 0.28 0.30 92.6 71.7 0.4446 0.4075 90 102 93.3 91.0 285.3 9090.516 2801 0.31 0.37 0.30 0.33 93.5 75.1 0.4522 0.4095 91 103 94.3 92.1281.1 873 0.510 2702 0.68 0.32 0.31 0.37 94.4 78.4 0.4609 0.4126 91 10395.3 93.0 276.9 833 0.503 2599 −0.1 0.27 0.32 0.41 95.0 80.1 0.46810.412 91 104 96.2 93.8 272.0 801 0.497 2509 0.66 0.23 0.33 0.44 95.782.5 0.4774 0.4156 92 103 97.0 94.4 268.1 758 0.488 2403 0.46 0.18 0.330.48 96.3 83.5 0.4867 0.4161 92 103 97.7 94.9 262.9 717 0.479 2296 −0.090.14 0.33 0.52 96.6 83.4 0.4959 0.4149 92 104 98.3 95.0 257.2 677 0.4692203 −0.18 0.11 0.33 0.57 96.7 82.9 0.5049 0.4146 91 104 98.6 94.9 252.1636 0.459 2099 0.19 0.07 0.32 0.61 96.8 81.9 0.5165 0.4152 92 103 98.794.5 246.4 585 0.444 2010 −0.28 0.04 0.30 0.66 96.4 79.4 0.525 0.4126 90104 98.5 93.8 241.0 547 0.431 1902 −0.37 0.01 0.27 0.72 95.8 75.6 0.53660.4101 89 103 97.7 92.4 234.3 494 0.413 1797 −0.12 0.00 0.23 0.77 94.970.8 0.5493 0.4078 88 102 96.5 90.5 227.6 436 0.389

Table 8 shows exemplary luminophoric mediums suitable for the recipientluminophoric mediums for the red channels of this Example, using theCompositions A-F from Model 1 or Model 2 as described in Tables 3 and 4.

TABLE 8 Volumetric Ratios - Using “Model 1” Compositions from Tables 3and 4 Comp. Comp. Comp. Comp. Comp. Comp. A B C D E F Matrix Red Blend 113.99 26.57 59.44 Red Blend 2 17.20 8.94 73.86 Red Blend 3 20.56 18.380.02 61.04 Red Blend 4 5.55 9.40 22.00 63.05 Red Blend 5 2.47 29.1647.28 21.08

Light rendering properties were calculated for commercially availabletunable white light systems. Table 9 shows color-rendering and circadianperformance characteristics of a three-channel device having white,green, and red channels, LED Engin's LuxiTune™ Tunable White LightEngine For Halogen-style Dimming LTC-83T1xx-0HD1 (LED Engin, Inc., SanJose, Calif.), for a representative selection of white light colorpoints near the Planckian locus. Table 10 shows color-rendering andcircadian performance characteristics of a five-channel device havingwhite, blue, red, lime, and amber channels, Lumenetix's Araya® ColorTuning Module (CTM) (Lumenetix, Scotts Valley, Calif.), for arepresentative selection of white light color points near the Planckianlocus.

TABLE 9 circadian power circadian CCT duv Ra R9 Rf Rg [mW] flux CER CAFEML CLA CS 2957.1 −0.99 88.14 60.12 87 109 0.001 0.0003 113.4262 0.35850.49788 914 0.517 2832.5 −1.11 87.55 58.33 87 109 0.001 0.0002 106.44560.3361 0.4747 868 0.509 2741.4 −0.58 87.23 58.96 87 110 0.001 0.000299.9416 0.3140 0.45283 824 0.501 2608.7 −0.52 86.92 60.56 86 111 0.0010.0002 92.4105 0.2885 0.42649 772 0.491 2506.3 −0.26 86.69 62.57 86 1110.001 0.0001 85.8899 0.2670 0.40442 727 0.481 2303.2 −0.25 85.21 65.6585 112 0.000 0.0001 74.0231 0.2303 0.36621 652 0.463 2040.7 −2.87 80.8466.23 80 106 0.000 0.0000 64.8177 0.2083 0.33513 595 0.447 1901.4 −3.3679.19 71.22 77 118 0.000 0.0000 58.1408 0.1897 0.31196 552 0.433 1782.21.95 82.13 92.16 78 99 0.000 0.0000 39.1467 0.1230 0.24983 425 0.384

TABLE 10 circadian power circadian CCT duv Ra R9 Rf Rg [mW] flux CER CAFEML CLA CS 2977 −0.25 96.09 90.52 93 104 0.001 0.0003 116.7513 0.38650.55372 1011 0.532 2872 −1.82 96.90 96.13 94 104 0.001 0.0003 111.66080.3787 0.54171 991 0.529 2744 −1.99 97.00 88.16 93 103 0.001 0.0002104.3151 0.3520 0.50898 929 0.52 2560 −0.56 96.61 89.42 93 104 0.0010.0001 90.5068 0.3020 0.45693 825 0.502 2454 −0.64 95.93 94.25 93 1040.000 0.0001 84.5877 0.2838 0.43942 790 0.495 2287 −1.48 95.11 93.38 90106 0.000 0.0001 76.2707 0.2567 0.40294 722 0.48 2011 0.81 93.56 93.0989 101 0.000 0.0000 55.2737 0.1859 0.33012 578 0.441 1834 2.10 90.6483.00 82 90 0.000 0.0000 43.3134 0.1437 0.2831 484 0.41

Tables 11 and 12 show exemplary luminophoric mediums suitable for therecipient luminophoric mediums for the red channels of this Example,using the Compositions A-F from Model 1 or Model 2 as described inTables 3 and 4.

TABLE 11 Volumetric Ratios - Using “Model 1” Compositions from Tables 3and 4 Comp. Comp. Comp. Comp. Comp. Comp. A B C D E F Matrix Red Blend 11.66 24.23 74.11 Red Blend 2 0.07 15.34 7.90 76.70 Red Blend 3 1.9624.72 73.32 Red Blend 4 3.43 26.48 70.10 Red Blend 5 21.36 1.70 76.94Red Blend 6 0.80 24.49 1.22 73.49 Red Blend 7 0.22 12.74 11.75 75.28

TABLE 12 Volumetric Ratios - Using “Model 2” Compositions from Tables 3and 4 Comp. Comp. Comp. Comp. Comp. Comp. A B C D E F Matrix Red Blend 80 0.58 16.23 83.19 Red Blend 9 0.42 0 16.63 82.95 Red Blend 10 1.79 3.0917.6 77.52

Example 4

Exemplary luminophoric mediums suitable for the recipient luminophoricmediums for the red channels of the disclosure were modeled, using theCompositions A-F from Model 1 or Model 2 as described in Tables 3 and 4.Tables 13 and 14 show exemplary suitable luminophoric mediums that canbe used in the red channels.

TABLE 13 Volumetric Ratios - Using “Model 1” Compositions from Tables 3and 4 Comp. Comp. Comp. Comp. Comp. Comp. A B C D E F Matrix Red Blend11.66 21.77 66.57 Red Blend 5.59 17.46 7.21 69.74 Red Blend 13.17 25.4561.38 Red Blend 6.47 7.75 24.90 60.88 Red Blend 16.55 8.34 75.11 RedBlend 2.37 24.60 11.89 61.13 Red Blend 4.57 16.51 12.47 66.44 Red Blend2.18 20.26 77.55 Red Blend 0.40 13.83 5.57 80.20 Red Blend 2.57 20.9376.50 Red Blend 0.68 2.15 22.07 75.10 Red Blend 17.50 2.11 80.40 RedBlend 1.62 20.45 0.85 77.07 Red Blend 0.47 11.38 9.48 78.67 Red Blend2.12 26.06 71.82 Red Blend 0.24 16.36 9.03 74.37 Red Blend 2.43 26.6870.89 Red Blend 1.02 1.64 28.61 68.72 Red Blend 22.60 2.22 75.19 RedBlend 1.11 26.37 1.45 71.07 Red Blend 0.38 13.79 12.99 72.84

TABLE 14 Volumetric Ratios - Using “Model 2” Compositions from Tables 3and 4 Comp. Comp. Comp. Comp. Comp. Comp. A B C D E F Matrix Red Blend4.02 13.36 82.62 Red Blend 3.25 15.67 81.08 Red Blend 16.56 15.37 16.8851.19 Red Blend 0.74 14.13 85.13 Red Blend 0.6 14.65 84.75 Red Blend3.07 3.52 14.75 78.66 Red Blend 0.74 17.04 82.22 Red Blend 0.58 17.5281.90 Red Blend 2.3 3.97 18.94 74.79

Those of ordinary skill in the art will appreciate that a variety ofmaterials can be used in the manufacturing of the components in thedevices and systems disclosed herein. Any suitable structure and/ormaterial can be used for the various features described herein, and askilled artisan will be able to select an appropriate structures andmaterials based on various considerations, including the intended use ofthe systems disclosed herein, the intended arena within which they willbe used, and the equipment and/or accessories with which they areintended to be used, among other considerations. Conventional polymeric,metal-polymer composites, ceramics, and metal materials are suitable foruse in the various components. Materials hereinafter discovered and/ordeveloped that are determined to be suitable for use in the features andelements described herein would also be considered acceptable.

When ranges are used herein for physical properties, such as molecularweight, or chemical properties, such as chemical formulae, allcombinations, and subcombinations of ranges for specific exemplartherein are intended to be included.

The disclosures of each patent, patent application, and publicationcited or described in this document are hereby incorporated herein byreference, in its entirety.

Those of ordinary skill in the art will appreciate that numerous changesand modifications can be made to the exemplars of the disclosure andthat such changes and modifications can be made without departing fromthe spirit of the disclosure. It is, therefore, intended that theappended claims cover all such equivalent variations as fall within thetrue spirit and scope of the disclosure.

What is claimed:
 1. A method of generating white light, the methodcomprising: producing light from a first light emitting diode (“LED”)string that comprises a blue LED with a peak wavelength of between about405 nm and about 470 nm; producing light from a second light emittingdiode (“LED”) string that comprises a blue LED with a peak wavelength ofbetween about 405 nm and about 470 nm; producing light from a thirdlight emitting diode (“LED”) string that comprises a blue LED with apeak wavelength of between about 405 nm and about 470 nm; passing thelight produced by each of the first, second, and third LED stringsthrough one of a plurality of respective luminophoric mediums to producea first unsaturated light, a second unsaturated light, and a thirdunsaturated light, respectively; combining the first unsaturated light,the second unsaturated light, and the third unsaturated light togetherinto a fourth unsaturated light; wherein the second unsaturated lighthas a spectral power distribution is 100% for wavelengths between 621 nmto 660 nm, and between 1.8% to 74.3% for wavelengths between 661 nm to700 nm; and wherein fourth unsaturated light corresponds to at least oneof a plurality of points along a predefined path near the black bodylocus in the 1931 CIE Chromaticity Diagram within a 7-step MacAdamellipse around any point on the black body locus having a correlatedcolor temperature between about 1800 K and about 3200 K.
 2. The methodof claim 1, wherein the first unsaturated light has a first color pointwithin a white color range defined by a polygonal region on the 1931 CIEChromaticity Diagram defined by the following ccx, ccy colorcoordinates: (0.4006, 0.4044), (0.3736, 0.3874), (0.3670, 0.3578),(0.3898, 0.3716).
 3. The method of claim 1, wherein the white colorrange comprises a single 5-step MacAdam ellipse with center point(0.3818, 0.3797) with a major axis “a” of 0.01565, minor axis “b” of0.00670, with an ellipse rotation angle θ of 52.70° relative to a lineof constant ccy values.
 4. The method of claim 1, wherein the red colorrange comprises a region on the 1931 CIE Chromaticity Diagram defined bya 20-step MacAdam ellipse at 1200 K, 20 points below the Planckianlocus.
 5. The method of claim 1, wherein the cyan color range comprisesa region on the 1931 CIE Chromaticity Diagram defined by region boundedby (0.360, 0.495), (0.371, 0.518), (0.388, 0.522), and (0.377, 0.499).6. The method of claim 1, wherein the white color range comprises asingle 3-step MacAdam ellipse with center point (0.3818, 0.3797) with amajor axis “a” of 0.00939, minor axis “b” of 0.00402, with an ellipserotation angle θ of 53.7° relative to a line of constant ccy values. 7.The method of claim 1, wherein the method comprises generating fourthunsaturated light corresponding to a plurality of points along thepredefined path with the light generated at each point having light withone or more of Rf greater than or equal to about 88, Rg greater than orequal to about 95 and less than or equal to about
 105. 8. The method ofclaim 1, wherein the method comprises generating fourth unsaturatedlight corresponding to a plurality of points along the predefined pathwith the light generated at each point having light with one or more ofRf greater than or equal to about 85, Rg greater than or equal to about90 and less than or equal to about
 110. 9. The method of claim 1,wherein the method comprises generating fourth unsaturated lightcorresponding to a plurality of points along the predefined path withthe light generated at each point having light with one or more of Rfgreater than or equal to about 88, Rg greater than or equal to about 96and less than or equal to about
 104. 10. The method of claim 1, whereinthe method comprises generating fourth unsaturated light correspondingto a plurality of points along the predefined path with the lightgenerated at each point having light with one or more of: Rf greaterthan or equal to about 88; and Rg greater than or equal to about 96 andless than or equal to about
 104. 11. The method of claim 1, wherein thesecond unsaturated light has a spectral power distribution that fallsbetween 0.0% to 14.8% for wavelengths between 380 nm to 420 nm, between2.1% to 15% for wavelengths between 421 nm to 460 nm, between 2.0% to6.7% for wavelengths between 461 nm to 500 nm, between 1.4% to 12.2% forwavelengths between 501 nm to 540 nm, between 8.7% to 24.7% forwavelengths between 541 nm to 580 nm, between 48.5% and 102.8% forwavelengths between 581 nm to 620 nm, 100% for wavelengths between 621nm to 660 nm, between 1.8% to 74.3% for wavelengths between 661 nm to700 nm, between 0.5% to 29.5% for wavelengths between 701 nm to 740 nm,and between 0.3% to 9.0% for wavelengths between 741 nm to 780 nm. 12.The method of claim 1, wherein the third unsaturated light has aspectral power distribution that falls between 3.9% to 130.6% forwavelengths between 380 nm to 420 nm, 100% for wavelengths between 421nm to 460 nm, between 112.7% to 553.9% for wavelengths between 461 nm to500 nm, between 306.2% to 5472.8% for wavelengths between 501 nm to 540nm, between 395.1% to 9637.9% for wavelengths between 541 nm to 580 nm,between 318.2% to 12476.9% for wavelengths between 581 nm to 620 nm,between 245% to 13285.5% for wavelengths between 621 nm to 660 nm,between 138.8% to 6324.7% for wavelengths between 661 nm to 700 nm,between 39.5% to 1620.3% for wavelengths between 701 nm to 740 nm, andbetween 10.3% to 344.7% for wavelengths between 741 nm to 780 nm. 13.The method of claim 1, wherein the second unsaturated light has aspectral power distribution that falls between 0% to 0.1% forwavelengths between 380 nm to 420 nm, between 2.3% to 2.7% forwavelengths between 421 nm to 460 nm, between 4.3% to 5% for wavelengthsbetween 461 nm to 500 nm, between 9.5% to 10.2% for wavelengths between501 nm to 540 nm, between 24.6% to 24.7% for wavelengths between 541 nmto 580 nm, between 60.4% to 61% for wavelengths between 581 nm to 620nm, 100% for wavelengths between 621 nm to 660 nm, between 51.5% to71.7% for wavelengths between 661 nm to 700 nm, between 12.4% to 27.8%for wavelengths between 701 nm to 740 nm, and between 2.4% to 8.4% forwavelengths between 741 nm to 780 nm.
 14. The method of claim 1, whereinthe third unsaturated light has a spectral power distribution that fallsbetween 3.9% to 30.6% for wavelengths between 380 nm to 420 nm, 100% forwavelengths between 421 nm to 460 nm, between 112.7% to 553.9% forwavelengths between 461 nm to 500 nm, between 306.2% to 2660.6% forwavelengths between 501 nm to 540 nm, between 395.1% to 4361.9% forwavelengths between 541 nm to 580 nm, between 318.2% to 3708.8% forwavelengths between 581 nm to 620 nm, between 245% to 2223.8% forwavelengths between 621 nm to 660 nm, between 138.8% to 712.2% forwavelengths between 661 nm to 700 nm, between 39.5% to 285.6% forwavelengths between 701 nm to 740 nm, and between 10.3% to 99.6% forwavelengths between 741 nm to 780 nm.
 15. The method of claim 1, whereinthe method further comprises receiving input from one or more of an enduser of the semiconductor light emitting device and one or more sensorsmeasuring a characteristic associated with the performance of the firstLED string, the second LED string, or the third LED string.
 16. Themethod of claim 1, wherein the method comprises generating fourthunsaturated light corresponding to a plurality of points along thepredefined path, wherein: the light generated at points along about 85%of the predefined path has Rf greater than or equal to about 90; thelight generated at points along about 85% of the predefined path has Rggreater than or equal to about 95 and less than or equal to about 105;or both.
 17. The method of claim 1, wherein the method comprisesgenerating fourth unsaturated light corresponding to a plurality ofpoints along the predefined path with the light generated at each pointhaving light with one or more of Ra greater than or equal to about 90,R9 greater than or equal to about
 60. 18. The method of claim 1, whereinthe method comprises generating fourth unsaturated light correspondingto a plurality of points along the predefined path with the lightgenerated at each point having light with one or more of: Ra greaterthan or equal to about 90; and R9 greater than or equal to about
 60. 19.The method of claim 1, wherein the method comprises generating fourthunsaturated light corresponding to a plurality of points along thepredefined path, wherein: the light generated at points along about 85%of the predefined path has Ra greater than or equal to about 90; thelight generated at points along about 85% of the predefined path has R9greater than or equal to about 65; or both.
 20. The method of claim 1,wherein the red color range comprises a region on the 1931 CIEChromaticity Diagram defined by region bounded by lines connecting(0.576, 0.393), (0.583, 0.400), (0.604, 0.387), and (0.597, 0.380). 21.A semiconductor light emitting device, comprising: a first lightemitting diode (“LED”) string that comprises a first LED that has afirst recipient luminophoric medium that comprises a first luminescentmaterial; a second LED string that comprises a second LED that has asecond recipient luminophoric medium that comprises a second luminescentmaterial; a third LED string that comprises a third LED that has a thirdrecipient luminophoric medium that comprises a third luminescentmaterial; and a drive circuit; wherein the drive circuit is configuredto adjust the relative values of first, second, third, and fourth drivecurrents provided to the LEDs in the first, second, and third LEDstrings, respectively, to adjust a fourth color point of a fourthunsaturated light that results from a combination of the first, second,and third unsaturated light; wherein a combined light emitted by thefirst, second, and third LEDs and the first, second, and thirdluminophoric mediums together has a fourth color point that falls withina 7-step MacAdam ellipse around any point on the black body locus havinga correlated color temperature between about 1800 K and about 3200 K;and wherein the second unsaturated light has a spectral powerdistribution that is 100% for wavelengths between 621 nm to 660 nm andbetween 1.8% to 74.3% for wavelengths between 661 nm to 700 nm.
 22. Thesemiconductor light emitting device of claim 21, wherein the LEDs in thefirst, second, and third LED strings comprise blue LEDs having a peakwavelength between about 405 nm and about 485 nm.
 23. The semiconductorlight emitting device of claim 21, wherein the white color rangecomprises a region defined by a polygonal region on the 1931 CIEChromaticity Diagram defined by the following ccx, ccy colorcoordinates: (0.4006, 0.4044), (0.3736, 0.3874), (0.3670, 0.3578),(0.3898, 0.3716).
 24. The semiconductor light emitting device of claim21, wherein the white color range comprises a single 5-step MacAdamellipse with center point (0.3818, 0.3797) with a major axis “a” of0.01565, minor axis “b” of 0.00670, with an ellipse rotation angle θ of52.70° relative to a line of constant ccy values.
 25. The semiconductorlight emitting device of claim 21, wherein the red color range comprisesa region on the 1931 CIE Chromaticity Diagram defined by a 20-stepMacAdam ellipse at 1200 K, 20 points below the Planckian locus.
 26. Thesemiconductor light emitting device of claim 21, wherein the cyan colorrange comprises a region on the 1931 CIE Chromaticity Diagram defined byregion bounded by (0.360, 0.495), (0.371, 0.518), (0.388, 0.522), and(0.377, 0.499).
 27. The semiconductor light emitting device of claim 21,wherein the white color range comprises a single 3-step MacAdam ellipsewith center point (0.3818, 0.3797) with a major axis “a” of 0.00939,minor axis “b” of 0.00402, with an ellipse rotation angle θ of 53.7°relative to a line of constant ccy values.
 28. The semiconductor lightemitting device of claim 21, wherein the drive circuit is configured toadjust the fourth color point so that it falls within a 7-step MacAdamellipse around any point on the black body locus having a correlatedcolor temperature between about 1800 K and about 3200 K.
 29. Thesemiconductor light emitting device of claim 28, wherein the lightemitting device is configured to generate the fourth unsaturated lightcorresponding to a plurality of points along a predefined path with thelight generated at each point having light with one or more of Ragreater than or equal to about 90, R9 greater than or equal to about 60.30. The semiconductor light emitting device of claim 21, wherein thedrive circuit is configured to adjust the fourth color point so that itfalls within a 7-step MacAdam ellipse around any point on the black bodylocus having a correlated color temperature between about 1800 K andabout 3200 K; and wherein the light emitting device is configured togenerate the fourth unsaturated light corresponding to a plurality ofpoints along a predefined path with the light generated at each pointhaving light with one or more of: Ra greater than or equal to about 90;and R9 greater than or equal to about
 60. 31. The semiconductor lightemitting device of claim 21, wherein the second unsaturated light has aspectral power distribution that falls between 0.0% to 14.8% forwavelengths between 380 nm to 420 nm, between 2.1% to 15% forwavelengths between 421 nm to 460 nm, between 2.0% to 6.7% forwavelengths between 461 nm to 500 nm, between 1.4% to 12.2% forwavelengths between 501 nm to 540 nm, between 8.7% to 24.7% forwavelengths between 541 nm to 580 nm, between 48.5% and 102.8% forwavelengths between 581 nm to 620 nm, 100% for wavelengths between 621nm to 660 nm, between 1.8% to 74.3% for wavelengths between 661 nm to700 nm, between 0.5% to 29.5% for wavelengths between 701 nm to 740 nm,and between 0.3% to 9.0% for wavelengths between 741 nm to 780 nm. 32.The semiconductor light emitting device of claim 21, wherein the thirdunsaturated light has a spectral power distribution that falls between3.9% to 130.6% for wavelengths between 380 nm to 420 nm, 100% forwavelengths between 421 nm to 460 nm, between 112.7% to 553.9% forwavelengths between 461 nm to 500 nm, between 306.2% to 5472.8% forwavelengths between 501 nm to 540 nm, between 395.1% to 9637.9% forwavelengths between 541 nm to 580 nm, between 318.2% to 12476.9% forwavelengths between 581 nm to 620 nm, between 245% to 13285.5% forwavelengths between 621 nm to 660 nm, between 138.8% to 6324.7% forwavelengths between 661 nm to 700 nm, between 39.5% to 1620.3% forwavelengths between 701 nm to 740 nm, and between 10.3% to 344.7% forwavelengths between 741 nm to 780 nm.
 33. The semiconductor lightemitting device of claim 21, wherein the second unsaturated light has aspectral power distribution that falls between 0% to 0.1% forwavelengths between 380 nm to 420 nm, between 2.3% to 2.7% forwavelengths between 421 nm to 460 nm, between 4.3% to 5% for wavelengthsbetween 461 nm to 500 nm, between 9.5% to 10.2% for wavelengths between501 nm to 540 nm, between 24.6% to 24.7% for wavelengths between 541 nmto 580 nm, between 60.4% to 61% for wavelengths between 581 nm to 620nm, 100% for wavelengths between 621 nm to 660 nm, between 51.5% to71.7% for wavelengths between 661 nm to 700 nm, between 12.4% to 27.8%for wavelengths between 701 nm to 740 nm, and between 2.4% to 8.4% forwavelengths between 741 nm to 780 nm.
 34. The semiconductor lightemitting device of claim 21, wherein the third unsaturated light has aspectral power distribution that falls between 3.9% to 30.6% forwavelengths between 380 nm to 420 nm, 100% for wavelengths between 421nm to 460 nm, between 112.7% to 553.9% for wavelengths between 461 nm to500 nm, between 306.2% to 2660.6% for wavelengths between 501 nm to 540nm, between 395.1% to 4361.9% for wavelengths between 541 nm to 580 nm,between 318.2% to 3708.8% for wavelengths between 581 nm to 620 nm,between 245% to 2223.8% for wavelengths between 621 nm to 660 nm,between 138.8% to 712.2% for wavelengths between 661 nm to 700 nm,between 39.5% to 285.6% for wavelengths between 701 nm to 740 nm, andbetween 10.3% to 99.6% for wavelengths between 741 nm to 780 nm.
 35. Thesemiconductor light emitting device of claim 21, wherein the drivecircuit is responsive to input from one or more of an end user of thesemiconductor light emitting device and one or more sensors measuring acharacteristic associated with the performance of the semiconductorlight emitting device.
 36. A method of forming a light emittingapparatus, the method comprising: providing a substrate, mounting afirst LED, a second LED, and a third LED on the substrate, providingfirst, second, and third luminophoric mediums in illuminativecommunication with the first, second, and third LEDs, respectively,wherein a combined light emitted by the first, second, and third LEDsand the first, second, and third luminophoric mediums together has afourth color point that falls within a 7-step MacAdam ellipse around anypoint on the black body locus having a correlated color temperaturebetween about 1800 K and about 3200 K; and wherein the second LED andthe second luminophoric medium are configured to emit combined lighthaving a spectral power distribution that is 100% for wavelengthsbetween 621 nm to 660 nm, and between 1.8% to 74.3% for wavelengthsbetween 661 nm to 700 nm.
 37. The method of claim 36, wherein the firstLED and the first luminophoric medium are configured to emit combinedlight having a first color point within a white color range defined by apolygonal region on the 1931 CIE Chromaticity Diagram defined by thefollowing ccx, ccy color coordinates: (0.4006, 0.4044), (0.3736,0.3874), (0.3670, 0.3578), (0.3898, 0.3716); the second LED and thesecond luminophoric medium are configured to emit combined light havinga second color point within a red color range defined by the spectrallocus between the constant CCT line of 1600 K and the line of purples,the line of purples, a line connecting the ccx, ccy color coordinates(0.61, 0.21) and (0.47, 0.28), and the constant CCT line of 1600 K; andthe third LED and the third luminophoric medium are configured to emitcombined light having a third color point within a cyan color rangedefined by a line connecting the ccx, ccy color coordinates (0.18, 0.55)and (0.27, 0.72), the constant CCT line of 9000 K, the Planckian locusbetween 9000 K and 1800 K, the constant CCT line of 1800 K, and thespectral locus.
 38. The method of claim 36, wherein the first, second,and third LEDs and first, second, and third luminophoric mediums areprovided as phosphor-coated blue light emitting device chips.
 39. Themethod of claim 36, wherein one or more of the first, second, and thirdluminophoric mediums are provided in positions remotely located from thefirst, second, and third LEDs, respectively.
 40. The method of claim 39,wherein the first, second, and third luminophoric mediums are providedin positions remotely located from the first, second, and third LEDs,respectively.
 41. The semiconductor light emitting device of claim 21,wherein the drive circuit is configured to adjust the fourth color pointso that it falls within a 7-step MacAdam ellipse around any point on theblack body locus having a correlated color temperature between about1800 K and about 3200 K; and wherein the light emitting device isconfigured to generate the fourth unsaturated light corresponding to aplurality of points along a predefined path; wherein: the lightgenerated at points along about 85% of the predefined path has Ragreater than or equal to about 92; the light generated at points alongabout 85% of the predefined path has R9 greater than or equal to about70; or both.
 42. The method of claim 1, wherein the third LED stringcomprises a blue LED with a peak wavelength of between about 440 nm andabout 465 nm.
 43. The semiconductor light emitting device of claim 21,wherein the third LED string comprises a blue LED with a peak wavelengthof between about 440 nm and about 465 nm.
 44. The method of claim 36,wherein the third LED comprises a blue LED with a peak wavelength ofbetween about 440 nm and about 465 nm.
 45. The method of claim 1,wherein the first unsaturated light has a first color point within a7-step MacAdam ellipse around any point on the black body locus having acorrelated color temperature between about 3500 K and about 6500 K;wherein the second unsaturated light has a second color point within ared color range defined by the spectral locus between the constant CCTline of 1600 K and the line of purples, the line of purples, a lineconnecting the ccx, ccy color coordinates (0.61, 0.21) and (0.47, 0.28),and the constant CCT line of 1600 K; wherein the second unsaturatedlight has a spectral power distribution is 100% for wavelengths between621 nm to 660 nm, and between 1.8% to 74.3% for wavelengths between 661nm to 700 nm, and wherein the third unsaturated light has a third colorpoint within a cyan color range defined by a line connecting the ccx,ccy color coordinates (0.18, 0.55) and (0.27, 0.72), the constant CCTline of 9000 K, the Planckian locus between 9000 K and 1800 K, theconstant CCT line of 1800 K, and the spectral locus.
 46. Thesemiconductor light emitting device of claim 21, wherein wherein thefirst LED and first luminophoric medium together emit a firstunsaturated light having a first color point within a white color rangedefined by a polygonal region on the 1931 CIE Chromaticity Diagramdefined by the following ccx, ccy color coordinates: (0.4006, 0.4044),(0.3736, 0.3874), (0.3670, 0.3578), (0.3898, 0.3716); wherein the secondLED and second luminophoric medium together emit a second unsaturatedlight having a second color point within a red color range defined bythe spectral locus between the constant CCT line of 1600 K and the lineof purples, the line of purples, a line connecting the ccx, ccy colorcoordinates (0.61, 0.21) and (0.47, 0.28), and the constant CCT line of1600 K; and wherein the third LED and third luminophoric medium togetheremit a third unsaturated light having a third color point within a cyancolor range defined by a line connecting the ccx, ccy color coordinates(0.18, 0.55) and (0.27, 0.72), the constant CCT line of 9000 K, thePlanckian locus between 9000 K and 1800 K, the constant CCT line of 1800K, and the spectral locus.